Preparation of High-density YAG/ZrB2 Multi-phase Ceramics by Spark Plasma Sintering

Lian-Meng Zhang,Jie-Guang Song,Jun-Guo Li,Jian-Rong Song 한양대학교 세라믹연구소 2007 Journal of Ceramic Processing Research Vol.8 No.5

ZrB2 and YAG are widely applied because of some excellent properties, but ZrB2 is difficult to prepare as a high-density ceramic, and it is easily oxidized in high temperature air, which limits the application of ZrB2 materials. To obtain high-density for better oxidation resistance ZrB2 ceramic materials, in this paper, Al2O3 and Y2O3 are added into ZrB2 raw material to prepare high-density YAG/ZrB2 multi-phase ceramics by spark plasma sintering. Through the above analysis, it is proposed that 1600oC is regarded as a critical sintering temperature (Tc) to fabricate YAG/ZrB2 multi-phase ceramics. Only if the sintering temperature is higher than Tc, can a nearly full density composite be achieved. The microstructure of sintered YAG/ ZrB2 multi-phase ceramics after 4 minutes at 1600oC is a better compact, the density and relative density are 5.5865 g/cm3 and 99.40% respectively, which indicates that high-density YAG/ZrB2 multi-phase ceramics have been fabricated successfully. ZrB2 and YAG are widely applied because of some excellent properties, but ZrB2 is difficult to prepare as a high-density ceramic, and it is easily oxidized in high temperature air, which limits the application of ZrB2 materials. To obtain high-density for better oxidation resistance ZrB2 ceramic materials, in this paper, Al2O3 and Y2O3 are added into ZrB2 raw material to prepare high-density YAG/ZrB2 multi-phase ceramics by spark plasma sintering. Through the above analysis, it is proposed that 1600oC is regarded as a critical sintering temperature (Tc) to fabricate YAG/ZrB2 multi-phase ceramics. Only if the sintering temperature is higher than Tc, can a nearly full density composite be achieved. The microstructure of sintered YAG/ ZrB2 multi-phase ceramics after 4 minutes at 1600oC is a better compact, the density and relative density are 5.5865 g/cm3 and 99.40% respectively, which indicates that high-density YAG/ZrB2 multi-phase ceramics have been fabricated successfully.

Genetic Variations in TERT-CLPTM1L Genes and Risk of Lung Cancer in a Chinese Population

Zhao, Meng-Meng,Zhang, Yue,Shen, Li,Ren, Yang-Wu,Li, Xue-Lian,Yin, Zhi-Hua,Zhou, Bao-Sen Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

Background: This study was conducted to investigate the association between single nucleotide polymorphisms (SNPs) in telomerase reverse transcriptase (TERT) and cleft lip and palate transmembrane1-like (CLPTM1L) and lung cancer risk in a Chinese population. Methods: We performed a hospital-based case-control study, including 980 lung cancer cases and 1000 cancer-free controls matched for age and sex. Each case and control was interviewed to collect information by well-trained interviewers. A total of 5 ml of venous blood was collected for genotype testing of TERT rs2736098 and CLPTM1L rs401681 using TaqMan methodology. Results: The results revealed that the variant homozygote TERT rs2736098TT was associated with an increased risk of lung cancer (OR=2.017, 95%CI=1.518-2.681), especially lung adenocarcinoma (OR=2.117, 95%CI=1.557-3.043) and small cell carcinoma (OR=1.979, 95%CI: 1.174-3.334), compared with the TERT rs2736098CC genotype. Similar results were observed in non-smokers. Conclusion: The TERT rs2736098 polymorphism might affect the susceptibility to lung cancer in Chinese populations. The associations need to be verified in larger and different populations.

Robustness Analysis of a Flexible Cable-Strut Tensile Structure

Lian-meng Chen,Wei-feng Gao,Zhichao Jiang,Yi-yi Zhou,Fu-bo Zhang,Shi-lin Dong 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.5

Currently, the robustness analysis of structure is primarily related to rigid structures, and little has been done to study the robustness of spatial fl exible cable-strut tensile structures with larger span, more complex forms, lower redundancy, more sensitivity to unexpected interference such as construction deviations, etc. Based on the H ∞ theory, this paper starts with the fundamental theory and develops analysis method for the robustness of fl exible cable-strut tensile structures, and then the relationships between the structural robustness and some design parameters such as initial pre-stress level, load distribution form, structural span, cross-section area, rise-span ratio, etc. are analysed through a case study of a concrete cable-strut tensile structure in China. On this basis, the eff ects of construction errors such as element-length error and supporting node position error are further analysed. Finally, the importance of each kind of element is analysed by means of conceptual removal of element. The results show that the higher the initial pre-stress level, the larger the element cross-section, the smaller the structural span, the larger the rise-span ratio and the more uniform the load distribution, the stronger the structural robustness. In the limited construction error range, the element-length error and the supporting node position error have little eff ects on the robustness of the structure. The hoop cables are the more important elements and the elements in inner region of the structure are of comparatively lower importance in the cable dome structure in this study.

Determination of a Monitoring Scheme for Controlling Construction Errors of a Cable-strut Tensile Structure

Lian-meng Chen,Wei-feng Gao,Dong Hu,Yi-yi Zhou,Fu-bo Zhang,Shi-lin Dong 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.10

Construction errors are inevitable in real cable-strut tensile structures. Nevertheless, the relevant work, especially the monitoring scheme design work, to control the construction errors is lacking. At present, the monitoring schemes always lay out the monitored members in the places with great internal force or great deformation, do not consider the method to control the construction errors and do not explain the method to lay out the monitored members in fundamental theory. To address this situation, the element length error, which is an important construction error affecting the bearing performance, is considered as the factor variable and the fundamental equation of pre-stress deviation and element length error is derived firstly. Next the methods to express the pre-stress deviation, which are only derived from the active cable length errors or from both the active cable and passive cable length errors, are discussed. After that, based on the condition that the errors can be solved and compensated, the least number of monitored members is determined. Moreover, those members sensitive to cable length deviation of active cables are selected as monitored members. In order to evaluate the effect level caused by passive cable length deviation, two evaluation parameters Δ and ρ are further discussed. Finally, one cable-strut tensile structure example is employed to verify the proposed method and the results of the example studies indicate that the least necessary number of monitored members can be achieved for the accurate solution and compensation of active cable length deviations. Different members have different sensitivities to the change of the length in active cables and those members with great sensitivities can be chosen in prior as monitored members. The evaluation parameters Δ and ρ can be used to analyze the source of errors and to evaluate the error effect level caused by the passive cable length deviation.

Plasma Folate and Vitamin B ₁₂ Levels in Patients with Hepatocellular Carcinoma

Cui, Lian-Hua,Quan, Zhen-Yu,Piao, Jin-Mei,Zhang, Ting-Ting,Jiang, Meng-Hui,Shin, Min-Ho,Choi, Jin-Su MDPI 2016 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.17 No.7

<P>Folate and vitamin B<SUB>12</SUB> involved in the one-carbon metabolism may play a key role in carcinogenesis and progression of hepatocellular carcinoma (HCC) through influencing DNA integrity. The purpose of this study is to evaluate the association of plasma folate and vitamin B12 levels with HCC in a case-control study on 312 HCC patients and 325 cancer-free controls. Plasma concentrations of folate and vitamin B<SUB>12</SUB> in all the subjects were measured by electrochemiluminescence immunoassay. Meanwhile, the information of HCC patients’ clinical characteristics including tumor-node-metastasis (TNM) stage, tumor size and tumor markers were collected. The patients of HCC had significantly lower folate levels than those of controls; there was no significant difference in the mean of plasma vitamin B<SUB>12</SUB> levels. We also observed an inverse association between the levels of plasma folate and HCC: the adjusted odds ratios (OR) (95% confidence intervals (CI)) of HCC from the highest to lowest quartile of folate were 0.30 (0.15–0.60), 0.33 (0.17–0.65), and 0.19 (0.09–0.38). Compared to the subjects in the lowest quartile of plasma vitamin B<SUB>12</SUB>, only the subjects in the highest quartile of vitamin B<SUB>12</SUB> exhibited a significant positive relationship with HCC, the adjusted OR was 2.01 (95% CI, 1.02–3.98). HCC patients with Stage III and IV or bigger tumor size had lower folate and higher vitamin B<SUB>12</SUB> levels. There was no significant difference in the mean plasma folate levels of the HCC cases in tumor markers status (AFP, CEA and CA19-9 levels), whereas patients with higher CEA or CA19-9 levels retained significantly more plasma vitamin B<SUB>12</SUB> than those with normal-CEA or CA19-9 level. In conclusion, plasma folate and vitamin B<SUB>12</SUB> levels could be associated with HCC, and might be used as predictors of clinical characteristics of HCC patients. However, further prospective studies are essential to confirm the observed results.</P>

An Analysis of the "Blank Space" in Freehand Flower and Bird Painting from an Aesthetic Perspective

Lijuan Liu,Yue Zhang,Jie Meng,Xiaobo Lian,Jun Wei,Jingyuan Wang KOREA INSTITUTE FOR HUMANITIES AND SOCIAL SCIENCES 2023 Journal of Arts and Cultural Studies(ACS) Vol.2 No.2

Background: "Leave blank" is a unique expression technique in Chinese painting. It has the unique charm of Chinese national culture. This article analyzes the artistic "Blank Space" expression in freehand brushwork flower and bird paintings from an aesthetic perspective. In aesthetics field, artistic beauty is an essential category. It can also be seen as a study of the aesthetic relationship between humans and the objective world. The "Blank Space" in Chinese freehand flower and bird paintings is important in ancient Chinese art. Purpose: The word "Blank Space" is easily understood and is a commonly used expression technique in Chinese art. It has strong Chinese aesthetic characteristics. This article analyzes the connotation and significance of "Blank Space". It studies freehand brushwork, composition, expression, and formal beauty of “Blank Space”. It elaborates the aesthetic expression of “Blank Space” in freehand flower and bird paintings. Furthermore, it has created various artistic beauty that make people feel graceful, melodious, and melancholic, with endless aftertaste. Methods: Based on the literature, analyze the art of leaving white space in the painting from an aesthetic perspective. Understand and master the importance of leaving white space in freehand flower and bird paintings comprehensively and correctly. Results: The application of "Blank Space" in the painting reflects the aesthetic taste of Chinese painting. It is the unique charm of traditional Chinese art. The "Blank Space" artistic techniques enriches and develops the artistic style of Chinese freehand flower and bird painting. Conclusion: The artistic conception, implicit beauty, spatial sense, and rhythmic rhythm of the screen perfectly express the "blank" art of Chinese freehand brushwork of flowers and birds. Blank space art uses "Blank Space" as a carrier to render beautiful artistic conceptions with strong Chinese aesthetic characteristics. Most works combine virtual and real, bringing readers a higher aesthetic enjoyment. It expands the hierarchical layout of the space, leaving room for imagination.

Chinese herbal injections for coronavirus disease 2019 (COVID-19): A narrative review

Xiao-Bin Zhu,Meng Guo,Zhi-Hui Zhang,Li-Hua Sun,Lei Liu,Li-Juan Zhou,Chun-Lei Shan,Yi Yang,Lian-Di Kan,Liu-Cheng Li 한국한의학연구원 2021 Integrative Medicine Research Vol.10 No.4

Background The outbreak of Coronavirus disease 2019 (COVID-19) has caused more than 180 million infections and 3.9 million deaths. To date, emerging clinical evidence has shown the synergetic benefits of Chinese herbal injections in treating this contagious respiratory disease. This review aims to summarize and analyze the efficacy and safety of Chinese herbal injections in the therapy of COVID-19. Methods The literature from 3 electronic databases, PubMed, CNKI, and Web of Science, were searched using the search terms “COVID-19”, “SARS-CoV-2”, “traditional Chinese medicine”, “herb”, “herbal”, and “injection”. Then the identified articles were comprehensively evaluated. Results Limited data demonstrated that Chinese herbal injections could significantly improve the clinical outcomes of COVID-19 patients, especially in combination with conventional treatment strategies. The benefits of which were mainly associated with the relief of symptoms, prevention of secondary infection, regulation of inflammation and immune function. There was also evidence showing the inhibitory effects on SARS-CoV-2 replication in vitro. Nevertheless, available real-world data suggested the increased risk of adverse event. Furthermore, the defects of existing researches and the insights for discovering novel antiviral drugs were prospectively discussed. Conclusion Evidence-based advances revealed that Chinese herbal injections such as XueBiJing injection and ShenMai injection, exerted potent effects against COVID-19. Further laboratory researches and clinical evaluation are needed to gather scientific evidence on the efficacy and safety.

Solid State Reaction Synthesis and Thermoelectric Properties of Ag-Doped Mg₂Si_0.8Ge_0.2

Liu, Qiong Zhen,Zhang, Lian Meng,Shen, Qiang,Jiang, Hong Yi,Wang, Chuan Bin Trans Tech Publications, Ltd. 2006 Key engineering materials Vol.313 No.-

<P>By two-step solid state reaction, Mg2Si0.8Ge0.2 was successfully synthesized .The effect of Ag-doping concentration on the thermoelectric transport properties of p-type Mg2Si0.8Ge0.2 was investigated. With the increasing of Ag-doping concentration, the electrical conductivity σ and Seebeck coefficient α increase correspondingly over the measuring temperature range (300-800K).The peaks of the curves of Seebeck coefficient versus temperature shift towards the lower temperature .When the doping concentration of Ag is 16000ppm(nominal molar percent), the power factor P of Mg2Si0.8Ge0.2 reaches 4.4×10-4W/mK2 at 800K,obviously improved in comparison with the sample with no additive .</P>

Hydrothermal Synthesis of PbTiO3 Nanocrystals with a pH-Adjusting Agent of Ammonia Solution

Xinyi Li,Zhi-Xiong Huang,Lian-Meng Zhang,Dongyun Guo 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.5

The PbTiO3nanocrystals were synthesized by a hydrothermal method, and ammonia solution was firstly used as a pH-adjustingagent. The effect of ammonia concentration on formation and morphologies of PbTiO3nanocrystals was investigated. At low ammonia concentration (0–2.2 mol/L), no perovskite PbTiO3phase was formed. When the ammonia concentrationwas 4.4 mol/L, the rod-like PbTiO3nanocrystals with highly crystalline were successfully synthesized. As the ammoniaconcentration further increased to 13.2 mol/L, the flake-like PbTiO3nanocrystals were formed.

The Dynamic Mechanical Properties for Recycled Aggregate Concrete under Tensile-Compressive States

Zhen-Jun He,Zhi-qiang Wang,Meng-jia Ding,Zhen-wei Wang,Xiao-jie Zhang,Lian-shuo Liu 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.5

The experiments under biaxial tensile-compressive (T-C) complex stress were carried out for two kinds of substitution percentages of recycled coarse aggregate (RCA) on biaxial proportional loading (α = σ1:σ3 =1:0, 0: -1, 0.05: -1, 0.1: -1, 0.25: -1, 0.5: -1, 1: -1 and-1: -1) and four loading deformation rates of 10−5/s, 10−4/s , 10−3/s, and 10−2/s. The research was completed in the static-dynamic true triaxial machine. The experimental phenomena indicate the tensile failure appears in these specimens of recycled aggregate concrete (RAC) under biaxial T-C stress states. The dynamic mechanical behavior for RAC under biaxial T-C loadings was affected by the strain rates, stress ratios and its substitution percentages of RCA. Accompanied by the increase of strain rates, its strength of RAC is improved. As the tensile stress increases, its compressive strength decreases. The T-C strengths for RAC under biaxial T-C states are less than its corresponding uniaxial T-C strengths at a certain identical strain rates, respectively. Considering the effect of loading rates, a new tensile-compressive failure criterion is established under complex stress states.