An intelligent method to design die profile for rubber forming of complex curved flange part

Ling‑Yun Zhang,Shuai Zhou,Tian‑Zhang Zhao,Yi‑Pan Zeng 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.1

Rubber forming is an important forming process for the manufacture of aircraft sheet metal parts. The springback is one of the main defects in rubber forming. Classical springback compensation by displacement adjustment method using finite simulation is not satisfactory. In this research, the algorithms of compensating the arc and flange surface of complex curved flange with correction formula are proposed by experiment. The correction formula was developed based on the CATIA V5 R19 using Component Application Architecture. Compensate profile is presented including surface pick up, line pick up, division, compensation, extending, and trimming. The die profile of part with complex curved flanges in aircraft could be designed rapidly. It was found that the forming pressure has a little effect on the springback. This is within the tolerance limits of the part. The results reveal the method can achieve the industrial part precisely. The method is demonstrated on an aircraft wing rib part.

New Iterative Process for The Equation Involving Strongly Accretive Operators in Banach Spaces

Ling-yan Zeng,Jun Li,김종규 대한수학회 2007 대한수학회보 Vol.44 No.4

In this paper, under suitable conditions, we show that thenew class of iterative process with errors introduced by Li et al convergesstrongly to the unique solution of the equation involving strongly accre-tive operators in real Banach spaces. Furthermore, we prove that it isequivalent to the classical Ishikawa iterative sequence with errors.

NEW ITERATIVE PROCESS FOR THE EQUATION INVOLVING STRONGLY ACCRETIVE OPERATORS IN BANACH SPACES

Zeng, Ling-Yan,Li, Jun,Kim, Jong-Kyu Korean Mathematical Society 2007 대한수학회보 Vol.44 No.4

In this paper, under suitable conditions, we show that the new class of iterative process with errors introduced by Li et al converges strongly to the unique solution of the equation involving strongly accretive operators in real Banach spaces. Furthermore, we prove that it is equivalent to the classical Ishikawa iterative sequence with errors.

Evolution of Tensile Properties of Compacted Red Clay under Wet and Dry Cycles

Ling Zeng,Hui-Cong Yu,Qian-Feng Gao,Jie Liu,Zi-Han Liu 대한토목학회 2022 KSCE Journal of Civil Engineering Vol.26 No.2

Tensile strength is an important soil parameter that affects the stability of structures built on clayey soils. This paper presents an experimental study of the change of tensile properties of red clay during wet-dry cycles. Cyclic wet-dry tests were performed on compacted red clay specimens with different initial water contents and dry densities. Direct tensile tests and Brazilian split tests were then conducted on these specimens to determine the soil strengths. The effects of initial water content, initial dry density, number of wet-dry cycles, and crack rate on the tensile properties of red clay were investigated. The results demonstrate that the tensile strength of red clay is generally 1.566 times the splitting strength. Both the tensile strength and splitting strength are negatively correlated with the initial water content but are positively correlated with the initial dry density. Because of the presence of desiccation cracks, the tensile strength goes on reducing under wet-dry cycles. The tensile strength can be expressed by a power function of the initial water content, initial dry density, and crack rate. The proposed equation is useful to evaluate the tensile strength of cracked soils subjected to wet-dry cycles.

The Effect of Herb-Partition Moxibustion on Toll-like Receptor 4 in Rabbit Aorta during Atherosclerosis

Zeng-Hui Yue,Xin-Qun He,Xiao-Rong Chang,Jian-Ling Yuan,Bao-Sheng Yu,Mi Liu,Ling Fu,Liang Zhang,Li-Chao Shang 사단법인약침학회 2012 Journal of Acupuncture & Meridian Studies Vol.5 No.2

Objective: To explore the mechanism of Toll-like receptor (TLR4) inhibition in the delay of formation of atherosclerosis by herb-partition moxibustion. Method: Seventy-five rabbits were randomly assigned to one of five groups: blank, atherosclerosis (AS) model, direct moxibustion, herb-partition moxibustion, and drug treatment. With the exception of the blank group, all rabbits were given a high-fat diet in addition to immunologic injury to create the AS model. The experiments were carried out for 16 weeks, at which time the aorta was removed from each rabbit. Immunohistochemical methods were used to detect the gray level of the aortic TLR4 to observe the immunologic competence of its antigens. Fluorescent quantitative polymerase chain reaction was used to detect the expression of TLR4 messenger RNA (mRNA) in the aorta. Results: The gray-scale value of TLR4 and the TLR4 mRNA expression significantly decreased (p < 0.05) in the direct moxibustion, herb-partition moxibustion, and drug treatment groups. Furthermore, the effects of the herb-partition moxibustion and drug treatment were superior to those of the direct moxibustion. Conclusion: Herb-partition moxibustion inhibits aortic TLR4 activity and mRNA expression,showing that herb-partition moxibustion delays the formation of atherosclerosis through the inhibition of TLR4 expression.

Structure and Performances of xLiFePO4/C·(1 − x)Li3V2(PO4)3/C Cathode for Lithium-Ion Batteries by Using Poly(vinyl alcohol) as Carbon Source

Chang-ling Fan,Wei-hua Zhang,Tao-tao Zeng,Ling-fang Li,Xiang Zhang,Shao-chang Han 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.11

Poly(vinyl alcohol), whose pyrolysis carbon possesses high conductivity of 8.88 × 10−1 S/cm, was used to synthesize xLiFePO4/C·(1 − x)Li3V2(PO4)3/C cathode. It was characterized by X-ray diffraction, scanning electron microscopy, conductivity, cyclic voltammetry, and galvanostatic charge and discharge experiments. Results show that LiFePO4/C and Li3V2(PO4)3/C coexists in the cathode. The particles sizes of 0.75LiFePO4/C·0.25Li3V2(PO4)3/C (x = 0.75) are much smaller than 100 nm due to the role of poly(vinyl alcohol). Its conductivity is 8.79 × 10−2 S/cm. The oxidative and reductive peaks in cyclic voltammetry are sharp and symmetrical. Their low potential gaps indicate that the extractions and insertions of lithium ion possess excellent reversibility. Its discharge capacities at 1 and 5 C are 141.1 and 100.1 mAh/g. The more Li3V2(PO4)3/C in cathode results in the deterioration of electrochemical performances due to its low theoretical capacity. It is concluded that poly(vinyl alcohol) is an effective carbon source in the preparation of xLiFePO4/C·(1 − x)Li3V2(PO4)3/C composite cathode with excellent performances.

Asparagus Polysaccharide and Gum with Hepatic Artery Embolization Induces Tumor Growth and Inhibits Angiogenesis in an Orthotopic Hepatocellular Carcinoma Model

Weng, Ling-Ling,Xiang, Jian-Feng,Lin, Jin-Bo,Yi, Shang-Hui,Yang, Li-Tao,Li, Yi-Sheng,Zeng, Hao-Tao,Lin, Sheng-Ming,Xin, Dong-Wei,Zhao, Hai-Liang,Qiu, Shu-Qi,Chen, Tao,Zhang, Min-Guang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

Liver cancer is one of leading digestive malignancies with high morbidity and mortality. There is an urgent need for the development of novel therapies for this deadly disease. It has been proven that asparagus polysaccharide, one of the most active derivates from the traditional medicine asparagus, possesses notable antitumor properties. However, little is known about the efficacy of asparagus polysaccharide as an adjuvant for liver cancer chemotherapy. Herein, we reported that asparagus polysaccharide and its embolic agent form, asparagus gum, significantly inhibited liver tumor growth with transcatheter arterial chemoembolization (TACE) therapy in an orthotopic hepatocellular carcinoma (HCC) tumor model, while significantly inhibiting angiogenesis and promoting tumor cell apoptosis. Moreover, asparagine gelatinous possessed immunomodulatory functions and showed little toxicity to the host. These results highlight the chemotherapeutic potential of asparagus polysaccharide and warrant a future focus on development as novel chemotherapeutic agent for liver cancer TACE therapy.

Cervical Cancer Mortality Trends in China, 1991-2013, and Predictions for the Future

Du, Pei-Ling,Wu, Ku-Sheng,Fang, Jia-Ying,Zeng, Yang,Xu, Zhen-Xi,Tang, Wen-Rui,Xu, Xiao-Ling,Lin, Kun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.15

Background: To analyze cervical cancer mortality trends in China from 1991-2013 and forecast the mortality distribution in future five years (2014-2018), and provide clues for prevention and treatment. Materials and Methods: Mortality data for cervical cancer in China from 1991 to 2013 were used to describe the epidemiological characteristics and distribution, including the trend of the standardized mortality rate, urban-rural differences, and age variation. Trend-surface analysis was used to analyze the geographical distribution of mortality. Curve estimation, time series, gray modeling, and joinpoint regression were performed to predict and forecast mortality trends. Results: In recent years, the mortality rate of cervical cancer has increased, and there is also a steady increase in the incidence from 2003 to 2013 in China. Mortality rates in rural areas are higher than in urban areas. The mortality dramatically increases in the 40+ yr age group, reaching a peak in the >85 yr age group. In addition, geographical analysis showed that the cervical cancer mortality increased from the southwest to west-central and from the southeast to northeast of the country. Conclusions: The incidence rate and the mortality rate are increasing from 1991 to 2013, and the predictions show this will continue in the future. Thus, implementation of prevention and management programs for cervical cancer are necessary in China, especially for rural areas, young women in urban areas, and high risk regions (the west-central).

Gefitinib Alone or with Concomitant Whole Brain Radiotherapy for Patients with Brain Metastasis from Non-small-cell Lung Cancer: A Retrospective Study

Zeng, Yin-Duo,Zhang, Li,Liao, Hai,Liang, Ying,Xu, Fei,Liu, Jun-Ling,Dinglin, Xiao-Xiao,Chen, Li-Kun Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Background: Gefitinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), is used both as a single drug and concurrently with whole brain radiotherapy (WBRT) the standard treatment for brain metastases (BM), and is reported to be effective in a few small studies of patients with BM from non-small-cell lung cancer (NSCLC). However, no study has compared the two treatment modalities. This retrospective analysis was conducted to compare the efficacy of gefitinib alone with gefitinib plus concomitant WBRT in treatment of BM from NSCLC. Methods: We retrospectively reviewed 90 patients with BM from NSCLC who received gefitinib alone (250mg/day, gefitinib group) or with concomitant WBRT (40Gy/20f/4w, gefitinib-WBRT group) between September 2005 and September 2009 at Sun Yat-Sen University Cancer Center. Forty-five patients were in each group. Results: The objective response rate of BM was significantly higher in gefitinib-WBRT group (64.4%) compared with gefitinib group (26.7%, P<0.001). The disease control rate of BM was 71.1% in gefitinib-WBRT group and 42.2% in gefitinib group (P=0.006). The median time to progression of BM was 10.6 months in gefitinib-WBRT group and 6.57 months in gefitinib group (P<0.001). The median overall survival(OS) of gefitinib-WBRT and gefitinib alone group was 23.40 months and 14.83 months, respectively (HR, 0.432, P=0.002). Conclusion: Gefitinib plus concomitant WBRT had higher response rate of BM and significant improvement in OS compared with gefitinib alone in treatment of BM from NSCLC.

Protective effects of l-theanine on rats with dextran sulfate sodium-induced infl ammatory bowel disease

Ling Chen,Wen-jun Xiao,Qiong-xian Yan,Zhi-hua Gong,Sheng Zhang,Li Zeng,Ming Yang,Yan-he Zhou 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.8

The aim of this study is to evaluate the antiinflammatory and protective eff ects of L -theanine in infl ammatorybowel disease (IBD) and to identify the underlyingmolecular mechanisms. Rats were pre-treated with L -theanineat 0, 50, 200, or 800 mg/kg/day. IBD was induced inrats using dextran sulfate sodium (DSS). Histopathologicalanalysis suggests that L -theanine can suppress DSS-inducedIBD with signifi cant inhibition of infl ammation in large andsmall intestinal tissues. Moreover, the 200 mg/kg/day L -theanine-treated DSS group had higher body and small intestineweights, a lower disease activity index and expression ofinfl ammatory factors than the DSS group without pre-treatment. In RNA sequencing and tandem mass tag labelinganalyses, large number of mRNAs and proteins expressionlevel diff ered when compared with the DSS-induced ratswith and without 200 mg/kg/day L -theanine pre-treatment. Moreover, Kyoto Encyclopedia of Genes and Genomes pathwayanalysis indicates the anti-infl ammatory activities ofL -theanine in DSS-induced IBD, with a high representationof genes in “Cholesterol metabolism” and “Retinol metabolism”pathways. Analysis of protein–protein interaction networksfurther indicates the involvement of these two pathways. These studies suggest that medium-dose L -theaninepre-treatment could ameliorate DSS-induced IBD throughmolecular mechanisms involving cholesterol and retinolmetabolism.