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Microstructure and mechanical properties of 3D printed ceramics with different vinyl acetate contents

Rare Metals 2021年第11期40卷 3241-3250页

作者： He Li Yong-Sheng liu yan-song liu Qing-Feng Zeng Jing-Jing Liang Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China NPU-SAS Joint Research Center of Advanced Ceramics Northwestern Polytechnical UniversityXi’an 710072China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

Stereolithography(SL)-based three-dimensional(3D) printing technique is an efficient method for the fabrication of alumina *** alumina slurry is difficult to obtain due to the barrier between hydrophilic alumina and oleophilic *** not only requires that the ceramic slurry possessed low viscosity and uniformity,but also requires that the slurry could complete the photocuring *** this study,vinyl acetate was added in the ceramic slurry as a bridge to connect alumina and resin,and the effects of vinyl acetate content on the microstructure and mechanical properties of the alumina ceramics were systematically *** results showed that the alumina ceramics were composed of three types of particles which included large aggregates,individual particles,and long-columnshaped *** shrinkage,bulk density,and crystallite size of the ceramics increased with the increase in vinyl acetate *** open porosity decreased with the increase in vinyl acetate *** flexural strength of the ceramics first increased and subsequently decreased with the increase in vinyl acetate *** shrinkage in Z direction was much greater than that in X or Y *** on the above results,the optimum vinyl acetate content for alumina slurry was 10 wt%,which resulted in sintered ceramic with the shrinkage of 15.6% in X direction,13.5% in Ydirection,21.9% in Z direction,bulk density of 1.9 g·cm^(-3),open porosity of 50.1%,and flexural strength of 24.4 *** sintered ceramics satisfy the requirement of alumina ceramic cores.

关键词： Stereolithography Alumina ceramics Vinyl acetate Microstructure Mechanical properties

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Structure,phase evolution and properties of Ta films deposited using hybrid high-power pulsed and DC magnetron co-sputtering

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Chinese Physics B 2022年第6期31卷 557-562页

作者： Min Huang yan-song liu Zhi-Bing He Yong Yi Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China

Crystalline phase and microstructure control are critical for obtaining desired properties of Ta films deposited by magnetron ***,phase evolution and properties of Ta films deposited by using hybrid high power impulse magnetron sputtering(HiPIMS)and direct current magnetron sputtering(DCMS)under different fractions of DCMS power were investigated,where Ta ion to Ta neutral ratios of the deposition flux were *** results revealed that the number of Ta ions arriving on the substrate/growing film plays an important role in structure and phase evolution of Ta *** can effectively avoid the unstable arc discharge under low pressure and show a higher deposition rate by combining HiPIMS and DCMS compared with only ***,the high hardnessα-Ta films can be directly deposited by hybrid co-sputtering compared to those prepared by *** the co-sputtering technology,pureα-Ta phase films with extremely fine,dense and uniform crystal grains were obtained,which showed smooth surface roughness(3.22 nm),low resistivity(38.98μ?·cm)and abnormal high hardness(17.64 GPa).

关键词： hybrid sputtering tantalum thin film structure hardness

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Facile synthesis and cytotoxicity of 5-C-alkylates of 20(S)-camptothecins

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Chinese Chemical Letters 2008年第10期19卷 1202-1205页

作者： Di Zao Li Xian Dao Pan Hong yan liu song Wu Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beifing 100050 China

A series of 5-C-alkylating camptothecins have been synthesized by one-step method, and their in vitro antitumor activity was evaluated against six human cancer cell lines. The results showed that all 5-C-alkylates of ... 详细信息

关键词： Camptothecin Synthesis 5-C-Alkylate Antitumor activity

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Microstructure and properties of 3D-printed alumina ceramics with different heating rates in vacuum debinding

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Rare Metals 2020年第5期39卷 577-588页

作者： He Li Yong-Sheng liu yan-song liu Qing-Feng Zeng Ke-Hui Hu Jing-Jing Liang Zhi-Gang Lu Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi'an 710072China NPU-SAS Joint Research Center of Advanced Ceramics Northwestern Polytechnical UniversityXi'an 710072China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Tribology Tsinghua University Beijing 100084China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016China

The effect of heating rates during vacuum debinding on the microstructure and mechanical properties of alumina ceramics are discussed in this *** threedimensional(3D)-printed alumina ceramics examined in this study were found to have a layered structure,and interlayer spacing increased as the heating rate increased The pore diameter,shrinkage,flexural strength and hardness were found to decrease as the heating rate increased due to weak interfacial bonding between alumina particles Shrinkage was found to be much larger along the Z direction than along the X or Y directions due to the layer-bylayer forming mode during 3D printing.0.5°C·min-1is considered the optimum heating rate,yielding ceramics with interlayer spacing of 0.65 lm,shrinkage of 2.6%2.3%and 4.0%along the X,Y and Z directions,respectively,flexural strength of 27.5 MPa,hardness of29.8 GPa,Vickers hardness of HV 266.5,pore diameter of356.8 nm,bulk density of 2.5 g·cm-3,and open porosity of38.4%.The debinding procedure used in this study could be used to produce a high-quality ceramic which can be used for fabricating alumina ceramic cores.

关键词： Heating rate Vacuum debinding Alumina ceramics Three-dimensional(3D)printing Stereolithography

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Using CropSyst to Simulate Spring Wheat Growth in Black Soil Zone of Northeast China

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Pedosphere 2006年第3期16卷 354-361页

作者： WANG Zong-Ming, ZHANG Bai LI Xiao-yan song Kai-Shan liu Dian-Wei ZHANG Shu-Qing Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 （China）

Available water and fertilizer have been the main limiting factors for yields of spring wheat, which occupies a large area of the black soil zone in northeast China; thus, the need to set up appropriate models for scenario analysis of cropping system models has been increasing. The capability of CropSyst, a cropping system simulation model, to simulate spring wheat growth of a widely grown spring cultivar, 'Longmai 19', in the black soil zone in northeast China under different water and nitrogen regimes was evaluated. Field data collected from a rotation experiment of three growing seasons (1992-1994) were used to calibrate and validate the model. The model was run for 3 years by providing initial conditions at the beginning of the rotation without reinitializing the model in later years in the rotation sequence. Crop input parameters were set based on measured data or taken from CropSyst manual. A few cultivar-specific parameters were adjusted within a reasonable range of fluctuation. The results demonstrated the robustness of CropSyst for simulating evapotranspiration, aboveground biomass, and grain yield of 'Longmai 19' spring wheat with the root mean square errors being 7%, 13% and 13% of the observed means for evapotranspiration (ET), grain yield and aboveground biomass, respectively. Although CropSyst was able to simulate spring production reasonably well, further evaluation and improvement of the model with a more detailed field database was desirable for agricultural systems in northeast China.

关键词： black soil zone of northeast China cropping system simulation model validation spring wheat

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Prospective study found that peripheral lymph node sampling reduced the false-negative rate of sentinel lymph node biopsy for breast cancer

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Chinese Journal of Cancer 2016年第6期35卷 63-68页

作者： Chao Han Ben yang Wen-Shu Zuo yan-song liu Gang Zheng Li yang Mei-Zhu Zheng School of Medicine and Life Sciences University of Jinan-Shandong Academy of Medical SciencesJinan 250022ShangdongPRChina Department of Surgery Shandong Breast Center of Prevention and TreatmentShandong Cancer Hospital Affiliated to Shandong UniversityShandong Academy of Medical Sciences440 Jiyan RoadJinan 250117ShangdongPRChina

Background:Although sentinel lymph node biopsy(SLNB) can accurately predict the status of axillary lymph node(ALN) metastasis,the high false?negative rate(FNR) of SLNB is still the main obstacle for the treatment of patients who receive SLNB instead of ALN dissection(ALND).The purpose of this study was to evaluate the clinical significance of SLNB combined with peripheral lymph node(PLN) sampling for reducing the FNR for breast cancer and to discuss the effect of "skip metastasis" on the FNR of ***:At Shandong Cancer Hospital Affiliated to Shandong University between March 1,2012 and June 30,2015,the sentinel lymph nodes(SLNs) of 596 patients with breast cancer were examined using radiocolloids with blue dye ***,the SLNs were removed;then,the area surrounding the original SLNs was selected,and the visible lymph nodes in a field of 3–5 cm in diameter around the center(i.e.,PLNs) were removed,avoiding damage to the structure of the ***,ALND was *** SLNs,PLNs,and remaining ALNs underwent pathologic examination,and the relationship between them was ***:The identification rate of SLNs in the 596 patients was 95.1%(567/596);the metastasis rate of ALNs was 33.7%(191/567);the FNR of pure SLNB was 9.9%(19/191);and after the SLNs and PLNs were eliminated,the FNR was 4.2%(8/191),which was significantly decreased compared with the FNR before removal of PLNs(P Aected number(N) of SLNs,the patients were divided into four groups of N = 0.028).ccording to the det= 1,2,3,and ≥4;the FNR in these groups was 19.6,9.8,7.3,and 2.3%,*** the patients with removal of PLNs was significantly decreased compared with that before remo≤2 or val of P≤3 detected SLNs,the FNR afterLNs(N 3:12.2% vs.4.7%,P ≤ 2:14.0% vs.4.7%,P = 0.019;N ≤ nt(P = 0.021),whereas for patients with ≥4 detected SLNs,the decrease in FNR was not statistically significa= 1.000).In the entire cohorts,the "skip metastasis" rate was 2.5%(15/596);the FNR caused by "s

关键词： Breast cancer Sentinel lymph node biopsy Peripheral lymph node False-negative rate Skip metastasis

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Microstructure analysis of deep rock in Meilinmiao Mine

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 468-473页

作者： Ren-Liang SHAN Li-Wei song yan liu Wen-Feng ZHAO Hui-Xian CHEN School of Mechanics and Civil Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

SEM tests were conducted on four kinds of typical deep rocks in Meilinmiao Mine, and the micro properties were analyzed. The particles of gritstone are unbroken and particle diameter ranges from 80 lam to 400 pro, and the void between particles is wide. The macroscopic failure of gritstone is caused by breakage of the dung distributed between particles, and po- tassium feldspars contained in gritstone are not leached. The failure of medium sandstone is caused by micro cracks distributed in sandstone particles, and potassium feldspars are leached seriously, so the pores penetrate each other and there is close hy- draulic connection in medium sandstone. The particles of fine sandstone are broken, and the particle diameters range from 60 pm to 300 pm, which determines the pores have good connectivity between particles. The dolomites contained in fine sand- stone are corroded, and the micro fracture form belongs to inter-granular fracture. There are no particles and blocks in micro- structure of sandy mudstone, but there are diverse micro cracks. The failure of mudstone arises from the extension of micro cracks, and the microstructure is different from the other three kinds of sandstones obviously.

关键词： SEM test deep rock microstructure leaching crack

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Procalcitionin as a diagnostic marker to distinguish upper and lower gastrointestinal perforation

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World Journal of Gastroenterology 2017年第24期23卷 4422-4427页

作者： yang Gao Kai-Jiang Yu Kai Kang Hai-Tao liu Xing Zhang Rui Huang Jing-Dong Qu Si-Cong Wang Rui-Jin liu yan-song liu Hong-Liang Wang Department of Critical Care Medicine the Second Affiliated Hospital of Harbin Medical University Department of Critical Care Medicine the Cancer Hospital of Harbin Medical University Institute of Critical Care Medicine in Sino Russian Medical Research Center of Harbin Medical University Department of Critical Care Medicine the First Affiliated Hospital of Harbin Medical University

AIM To assess the accuracy of serum procalcitionin(PCT)as a diagnostic marker in verifying upper and lower gastrointestinal perforation(GIP).METHODS This retrospective study included 46 patients from the surgical intensive care unit(ICU)of the Second Affiliated Hospital of Harbin Medical University who were confirmed to have GIP between June 2013 and December *** and clinical patient data were recorded on admission to *** were divided into upper(n=19)and lower(n=27)GIP groups according to the perforation site(above or below Treitz ligament).PCT and WBC count was obtained before laparotomy and then compared between ***,the diagnostic accuracy of PCT was *** Patients with lower GIP exhibited significantly higher APACHE II score,SOFA score and serum PCT level than patients with upper GIP(P=0.017,0.004,and0.001,respectively).There was a significant positive correlation between serum PCT level and APACHE II score or SOFA score(r=0.715 and r=0.611,respectively),while there was a significant negative correlation between serum PCT level and prognosis(r=-0.414).WBC count was not significantly different between the two groups,and WBC count showed no significant correlation with serum PCT level,APACHE II score,SOFA score or *** area under the receiver operating characteristic curve of PCT level to distinguish upper or lower GIP was *** with a serum PCT level above 17.94 ng/d L had a high likelihood of lower GIP,with a sensitivity of 100%and a specificity of 42.1%.CONCLUSION Serum PCT level is a reliable and accurate diagnostic marker in identifying upper or lower GIP before laparotomy.

关键词： Procalcitionin White blood cell count Gastrointestinal perforation Sepsis APACHE II score SOFA score

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Modulatory effect of International standard Scalp Acupuncture on brain activation in the elderly as revealed by resting-state fMRI

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Neural Regeneration Research 2019年第12期14卷 2126-2131页

作者： Wai-Yeung Chung song-yan liu Jing-Chun Gao Yi-Jing Jiang Jing Zhang Shan-Shan Qu Ji-Ping Zhang Xiao-Long Tan Jun-Qi Chen Sheng-Xu Wang School of Traditional Chinese Medicine Southern Medical University Guangzhou Guangdong Province China School of Chinese Medicine The Chinese University of Hong Kong Shatin Hong Kong Special Administrative Region China Department of Neurology China-Japan Union Hospital of Jilin University Changchun Jilin Province China Department of Rehabilitation Medicine Third Affiliated Hospital of Southern Medical University Guangzhou Guangdong Province China Department of Rehabilitation Medicine Rehabilitation Hospital Fujian University of Traditional Chinese Medicine Fuzhou Fujian Province China Department of Medical Image Third Affiliated Hospital of Southern Medical University Guangzhou Guangdong Province China

The specific mechanisms by which acupuncture affects the central nervous system are unclear. In the International Standard Scalp Acupuncture system, acupuncture needles are applied at the middle line of the vertex, anterior parietal-temporal oblique line, and the posterior parietal-temporal oblique line. We conducted a single-arm prospective clinical trial in which seven healthy elderly volunteers (three men and four women;50–70 years old) received International Standard Scalp Acupuncture at MS5 (the mid-sagittal line between Baihui (DU20) and Qianding (DU21)), the left MS6 (line joining Sishencong (EX-HN1) and Xuanli (GB6)), and the left MS7 (line joining DU20 and Qubin (GB7)). After acupuncture, resting-state functional magnetic resonance imaging demonstrated changes in the fractional amplitude of low frequency fluctuations and regional homogeneity in various areas, showing remarkable enhancement of regional homogeneity in the bilateral anterior cingulate, left medial frontal gyrus, supramarginal gyrus, right middle frontal gyrus, and inferior frontal gyrus. Functional connectivity based on a seed region at the right middle frontal gyrus (42, 51, 9) decreased at the bilateral medial superior frontal gyrus. Our data preliminarily indicates that the international standard scalp acupuncture in healthy elderly participants specifcally enhances the correlation between the brain regions involved in cognition and implementation of the brain network regulation system and the surrounding adjacent brain regions. The study was approved by the Ethics Committee of the China-Japan Union Hospital at Jilin University, China, on July 18, 2016 (approval No. 2016ks043).

关键词： nerve regeneration resting-state functional magnetic resonance imaging International Standard Scalp Acupuncture acupoint specificity brain functional connectivity healthy elderly volunteers low frequency fluctuation regional homogeneity functional connectivity neural regeneration

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THE REACTION OF 2,2-DIHYDROPOLYFLUOROALKANOATES WITH C-NUCLEOPHILES

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Chinese Chemical Letters 1994年第6期5卷 485-486页

作者： Wei Yuan HUANG yan song liu (Shanghai Institute of Organic Chemistry, Chinese. Academy of Sciences Shanghai 200032)

Ethyl 2.2-dihydropolyfluoroalkanoates reacted with c-nucleophiles in the presence of base under mild conditions to give the corresponding dehydrofluorinationaddition products in good yields.

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