Mechanical Properties and Damage Characteristics of Coal-Rock Combination with Different Dip Angles

Zhi-Guo Xia,Shuai Liu,Zhuang Bian,Jinhu Song,Fan Feng,Ning Jiang 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.5

The effect of the dip angle of an interlayer coal seam on rock mass mechanical behavior and damage characteristics is seldom discussed. To address the lack of the existing research, a numerical simulation was conducted using the Particle Flow Code (PFC2D), and its damage to mechanical behavior, acoustic emission (AE) characteristics, and damage characteristics were analyzed. The outcomes exhibit the peak strength and elastic modulus of coal-rock combinations are between that of rock and coal. As the coal inclination angle rises, the elastic modulus and peak strength gradually decrease. AE model experiences the initial growth period, stable growth period, and rapid decline period. The value of AE hits and the generation of the AE signal is affected by the size of the inclination angle. The degree of damage to the coal-rock combination gradually rises as the angle rises. The damage process of the coal and rock composite sample encompasses an initial damage phase, damage stable evolution phase, accelerated damage phase, and a failure phase. The damage values of the stable evolution stage for varying dip angle models are also different. As the inclination angle increases, the damage value gradually increases, while the strain at the same damage value gradually decreases.

On-line Specific Growth Rate Control for Improving Reduced Glutathione Production in Saccharomyces cerevisiae

Zhi-Qiang Xiong,Mei-jin Guo,Ju Chu,Ying-ping Zhuang,Siliang Zhang 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.5

Reduced glutathione (GSH), the abundant bioactive tripeptide in most living cells, is widely used in pharmaceutical, food, and cosmetic industries. Specific growth rate (μ) is a key physiological parameter for GSH high-cell-density cultivation using microbial cell factories. Here, based on a biomass probe, an on-line μ feedback control was developed to regulate glucose feeding rate during the fed-batch phase for overproducing GSH in Saccharomyces cerevisiae. Compared with real-time μ controlled at 0.15/h, μ controlled at 0.2/h achieved yeast dry weight (120 g/L), GSH concentration (1.5 g/L), and intracellular GSH content (1.25%), which improved by 9, 150, and 129.1%, respectively. To our knowledge, this is the first report about on-line μ feedback control for GSH production. On-line μ control led to 59.38 mg/L/h of GSH productivity and 3.52 mg/g of GSH yield on glucose, which improved by 107.6 and 7.2%, respectively, in comparison with those of traditional ethanol feedback control (maintaining ethanol concentration at 1%). Taken together, the on-line μ feedback control is a promising method as an efficient alternative to conventional feed control techniques presently practiced in the GSH industry, and has the potential for the production of other valuable chemicals.

Review : Review on Research and Development of Shale Gas in China

( Li Zhuang ),( Kwang Yeom Kim ),( Zhi Xue Sun ),( Yan Chao Li ) 대한지질공학회 2015 지질공학 Vol.25 No.3

Shale gas reserves in China are large, although shale gas production is still in its infancy. This paper reviews Chinese national policies and guidelines related to shale gas development, in particular those related to recent progress in the development of shale gas reserves in Sichuan Province and Chongqing since February 2015. In addition, three large-scale R&D projects related to shale gas development, funded by the Government of China, are introduced, and the scope of the work in each project is described.

Springback prediction of the vee bending process for high-strength steel sheets

Daw-Kwei Leu,Zhi-Wei Zhuang 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.3

The precise prediction of springback is a key to assessing the accuracy of part geometry in sheet bending. A simplified approach is developed by considering the thickness ratio, normal anisotropy, and the strain-hardening exponent to estimate the springback of vee bending based on elementary bending theory. Accordingly, a series of experiments is performed to verify the numerical simulation. The calculation of the springback angle agrees well with the experiment, which reflects the reliability of the proposed model. The effects of process parameters such as punch radius, material strength, and sheet thickness on the springback angle are experimentally tested to determine the dominant parameters for reducing the springback angle in the sheet bending process for high-strength steel sheets. Moreover, the effects of the thickness ratio, normal anisotropy, and the strain-hardening exponent on the springback angle in the vee bending process for high-strength steel sheets are theoretically studied. Therefore, improving understanding on and control of the springback reduction of the vee bending process in practical applications is possible.

Relaxation Effect of Schisandra Chinensis Lignans on the Isolated Tracheal Smooth Muscle in Rats and Its Mechanism

Cheng-Cheng Lin,Zhi-Ying Xu,Bi-Han Wang,Wenyue Zhuang,Jinghui Sun,He Li,JianGuang Chen,Chunmei Wang 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.8

Schisandra chinensis (S. chinensis) is one of the core drugs used for relieving cough and asthma in traditional Chinese medicine. However, there are few basic studies on the treatment of respiratory diseases with S. chinensis in modern pharmacology, and the material basis and mechanism of its antiasthmatic effect are still unclear. Lignans are the main active components of S. chinensis. The aim of this study was to observe the relaxation effect of S. chinensis lignans (SCL) on the tracheal smooth muscle of rats by in vitro tracheal perfusion experiments, and to explore the mechanism by preincubation with L-type calcium channel blocker verapamil, four potassium channel blockers glibenclamide, tetraethylamine, 4-aminopyridine and barium chloride (BaCl2), β-adrenoceptor blocker propranolol, nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME), and the cyclooxygenase inhibitor indomethacin, respectively. The results showed that SCL (0.25–1.75 mg/mL) reduced the contraction of isolated tracheal smooth muscle induced by acetylcholine, the preincubation with verapamil and glibenclamide could attenuate the relaxation effect, whereas propranolol, 4-aminopyridine, BaCl2, tetraethylamine, L-NAME, and indomethacin had no such effect. These results suggest that SCL has a significant relaxation effect on the isolated tracheal smooth muscle of rats, and the mechanism may be related to the inhibition of extracellular calcium influx and intracellular calcium release from the sarcoplasmic reticulum, as well as the activation of ATP-sensitive potassium channels. These findings may provide a pharmacological basis for the traditional use of S. chinensis to treat asthma.

A New Rhodamine-based Fluorescent Probe for the Discrimination of Fe3+ from Fe2+

Qi-Hua You,Hua-Bin Huang,Zhi-Xia Zhuang,Xiao-Ru Wang,Wing-Hong Chan 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.11

A new rhodamine-based fluorescent probe for the discrimination of Fe3+ from Fe2+ has been designed and investigated. The probe shows an immediate visual color change in response to Fe3+ and Cu2+, while only Fe3+ triggers the fluorescent change of the probe. The existence of large amount of other metal ions shows negligible interference in the detection of Fe3+. The association constant Kass of 4.64 × 108 M−2 (R2 = 0.994) and 5.38 × 108 M−2 (R2 = 0.991) of the complex was derived from UV/Vis and fluorescence titration assuming 1:2 stoichiometry of probe–Fe3+ complex, respectively.

Prognostic Value of CD44 Variant exon 6 Expression in Non-Small Cell Lung Cancer: a Meta-analysis

Zhao, Shuang,He, Jin-Lan,Qiu, Zhi-Xin,Chen, Nian-Yong,Luo, Zhuang,Chen, Bo-Jiang,Li, Wei-Min Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Background: CD44v6 (CD44 variant exon 6) is the chief CD44 variant isoform regulating tumor invasion, progression, and metastasis. The prognostic value of CD44v6 expression in non small cell lung cancer (NSCLC) has been evaluated in many studies, but the results have remained controversial. Thus, we performed a meta-analysis of currently available studies to investigate the prognostic value of CD44v6 expression in NSCLC patients and the relationship between the expression of CD44v6 and clinicopathological features. Materials and Methods: Two independent reviewers searched the relevant literature in Pubmed, Medline and Embase from 1946 to January 2014. Overall survival (OS) and various clinicopathological features were collected from included studies. This meta-analysis was accomplished using STATA 12.0 and Revman 5.2 software. Pooled hazard ratios (HRs) with 95% confidence intervals (95%CIs) were calculated to estimate the effects. Results: A total of 921 NSCLC patients from ten studies met the inclusion criteria. The results showed that CD44v6 high expression was a prognostic factor for poor survival (HR=1.91, 95%CI=1.12-3.26, p<0.05). With respect to clinicopathological features, CD44v6 high expression was related to histopathologic type (squamous cell carcinoma versus adenocarcinoma: OR=2.72, 95%CI=1.38-5.38, p=0.004), and lymph node metastasis (OR=3.02, 95%CI=1.93-4.72, p<0.00001). Conclusions: Our results suggested CD44v6 high expression as a poor prognostic factor for NSCLC, and CD44v6 expression is associated with lymph node metastasis and histopathologic type. Therefore, CD44v6 expression can be used as a novel prognostic marker in NSCLC cases.

CHISELED NICKEL HYDROXIDE NANOPLATES GROWTH ON GRAPHENE SHEETS FOR LITHIUM ION BATTERIES

LEI-LEI TIAN,XIAN-YONG WEI,QUAN-CHAO ZHUANG,CHAO WU,RUI-LUN XIE,ZHI-MIN ZONG,YONG-LI CUI,SHI-GANG SUN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.6

The morphologies and structures of Ni(OH)2–graphene hybrid materials were tailored by using different mineralizers in this work. It was revealed that the synergic effects of the highly oxidized graphene sheets and the mineralizers played a crucial role in controlling the morphology and structure of the nanocomposites, and Na2CO3 is a very effective mineralizer for growing chiseled 2D nanoplates of Ni(OH)2 on graphene sheets. When produced with NaOH, fragmental Ni(OH)2 crystals with irregular shapes erratically decorated on graphene sheets. In contrast, chiseled Ni(OH)2 hexagonal nanoplates grown on graphene sheets were obtained when Na2CO3 was used as the mineralizer. These unique 2D–2D nanoarchitectures with higher contact area between the nanocrystals and graphene substrate can increase the interfacial interaction and then efficiently improve the structural stability of the composite material, thus exhibiting an enhanced Li storage capacity and excellent cycling performance of 562 mAh g-1 after the 36th cycle.

Diagnostic Potential of Strain Ratio Measurement and a 5 Point Scoring Method for Detection of Breast Cancer: Chinese Experience

Parajuly, Shyam Sundar,Lan, Peng Yu,Yun, Ma Bu,Gang, Yang Zhi,Hua, Zhuang Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Aim: To evaluate the differential diagnostic potential of lesion stiffness assessed by the sonoelastographic strain index ratio (SR) and elastographic color scoring system (UE) for breast lesions. Materials and Methods: Three hundred and forty two breast masses (158 benign and 184 malignant) from 325 consecutive patients (mean age 44.2 years; range 16-81)who had been scheduled for a sonographically guided core biopsy were examined proposed by Itoh et al, with scoring 1-3=benign and 4-5=malignant. Strain and area ratios of each lesion were calculated within the same machine. Histological diagnosis was used as the reference standard. The area under the curve (AUC) and cut-off point were obtained by receiver operating curve and the cross table Fischer Test was carried out for assessing diagnostic value. Sensitivity, specificity, PPV, NPV, accuracy and false-discovery rates were compared. Results: The mean strain ratios for benign and malignant lesions were 1.87 and 7.9 respectively. (P<0.0001). When a cutoff point of 3.54 was used, SR had a sensitivity of 94.6%, a specificity 94.3%, a PPV of 95.1%, an NPV of 93.7% and an accuracy of 94.4%. The AUC values were 0.90 for the 5 point scoring system (UE) and 0.96 for the strain index ratio. The overall diagnostic performance was SR method was better (P<0.05). Conclusions: Strain ratio measurement could be another effective predictor in elastography imaging besides 5 the point scoring system for differential diagnosis of breast lesions.

Risk Assessment of Breast Cancer in Guangdong, China: A Community-based Survey

Lin, Ying,Shao, Nan,Zhang, Yun-Jian,Wu, Zhuang-Hong,Li, Zhi-Bin,Ren, Ze-Fang,Wang, Shen-Ming Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

Objectives: Compared with Western countries, the incidence rates for breast cancer in China are still low. However, breast cancer appears to be hitting Chinese women at a much younger age, with a peak between 40 and 50 years. Furthermore, breast tumors of Asian women have molecular and genetic characteristics that are different from those of Caucasian women. Methods: A community-based study was designed to evaluate the relationship between lifestyles and breast cancer risk in Chinese women residing in Guangzhou. 16,314 subjects completed the questionnaire. Potential confounding factors included sociodemographic characteristics. Results: 33 individuals reported a history of breast cancer, yielding a prevalence rate of 202.3/100000. Associations between subjects' demographic and breast cancer risk factors were assessed. Breast cancer is associated with family history of breast cancer, X-rays received, benign breast disease and hyperlipoidemia or hypercholesteremia with elevated odds ratios. Conclusions: Family history of breast cancer, X-ray received benign breast disease and hyperlipoidemia or hypercholesteremia were significantly associated with risk of breast cancer and may havepotential for breast cancer risk assessment.