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| 1 | Selective laser melting(SLM)of CX stainless steel:Theoretical calculation,process optimization and strengthening mechanism显示文摘In the present work,selective laser melting(SLM)technology was utilized for manufacturing CX stainless steel samples under a series of laser parameters.The effect of laser linear energy density on the microstructure characteristics,phase distribution,crystallographic orientation and mechanical properties of these CX stainless steel samples were investigated theoretically and experimentally via scanning electron microscope(SEM),X-ray diffraction(XRD),electron backscatter diffraction(EBSD)and transmission electron microscope(TEM).Based on the systematic study,the SLM CX stainless steel sample with best surface roughness(Ra=4.05±1.8μm)and relative density(Rd=99.72%±0.22%)under the optimal linear density(η=245 J/m)can be obtained.SLM CX stainless steel was primarily constituted by a large number of fine martensite(α’phase)structures(i.e.,cell structures,cellular dendrites and blocky grains)and a small quantity of austenite(γphase)structures.The pre ferred crystallographic orientation(i.e.,<111>direction)can be determined in the XZ plane of the SLM CX sample.Furthermore,under the optimal linear energy density,the good combinations with the highest ultimate tensile strength(UTS=1068.0%±5.9%)and the best total elongation(TE=15.70%±0.26%)of the SLM CX sample can be attained.Dislocation strengthening dominates the strengthening mechanism of the SLM CX sample in as-built state. | Dongdong Dong Cheng Chang Hao Wang Xingchen Yan Wenyou Ma Min Liu Sihao Deng Julien Gardan Rodolphe Bolot Hanlin Liao | 2021 | Journal of Materials Science & Technology2021，，14： | 11 |
| 2 | An elevated preoperative serum calcium level is a significant predictor for positive peritoneal cytology in endometrial carcinoma显示文摘Objective:To evaluate preoperative serum calcium concentration and investigate the association between calcium level and positive peritoneal cytology in endometrial carcinoma(EC).Methods:A total of 510 patients who were diagnosed with EC and had surgery were initially enrolled in this study at Peking University People's Hospital between January 2012 and December 2016.Clinical characteristics and preoperative serum calcium,albumin,carbohydrate antigen(CA)125,CA19-9,carcinoembryonic antigen(CEA)were extracted from patient records and evaluated according to postoperative peritoneal cytology.Predictive factors were assessed with Cox univariate and multivariate analyses.Factors selected from multivariate analysis results were used to build a predictive model.Results:A total of 510 patients are identified in our database and 444 patients who fulfilled inclusion and exclusion criteria are included in this study.Univariate analysis revealed that ionized calcium concentration was closely related to positive peritoneal cytology,tumor grade and lymph-vascular space invasion(LVSI).Moreover,peritoneal cytology was significantly associated with hypertension,tubal ligation,serum CA125,CA19-9,CEA and ionized calcium level.Multivariate analysis revealed that albumin-adjusted calcium level,CA125 and tubal ligation were independent predictive factors of positive peritoneal cytology(P<0.05).A combination of ionized calcium level with the other two indexes yielded significantly great area under the curve(AUC=0.824).Conclusions:This study enhanced the value of preoperative ionized calcium level.We also identified several potential biomarkers to predict positive peritoneal cytology in EC patients before surgery. | Xingchen Li Yuan Cheng Yangyang Dong Boqiang Shen Xiao Yang Jiaqi Wang Jingyi Zhou Jianliu Wang | 2019 | Chinese Journal of Cancer Research2019，31，6： | 3 |
| 3 | DMD-based hyperspectra I microscopy with flexible multiline parallel scanning显示文摘As one of the most common hyperspearal microscopy(HSM)techniques,line-scanning HSM is currently utilized in many fields.However,its scanning efficiency is still considered to be inadequate since many biological and chemical processes occur too rapidly to be captured.Accordingly,in this work,a digital micromirror device(DMD)based on microelectromechanical systems(MEMS)is utilized to demonstrate a flexible multiline scanning HSM system.To the best of our knowledge,this is the first line-scanning HSM system in which the number of scanning lines N can be tuned by simply changing the DMD's parallel scanning units according to diverse applications.This brilliant strategy of effortless adjustability relies only on on-chip scanning methods and totally exploits the benefits of parallelization,aiming to achieve nearly an A/-time improvement in the detection efficiency and an N-time decrease in the scanning time and data volume compared with the single-line method under the same operating conditions.To validate this,we selected a few samples of different spectral wavebands to perform reflection imaging,transmission imaging,and fluorescence imaging with varying numbers of scanning lines.The results show the great potential of our DMD-based HSM system for the rapid development of cellular biology,material analysis,and so on.In addition,its on-chip scanning process eliminates the inherent microscopic architecture,making the whole system compact,lightweight,portable,and not subject to site constraints. | Xue Dong Geng Tong Xuankun Song Xingchen Xiao Yiting Yu | 2021 | Microsystems & Nanoengineering2021，7，5： | 1 |
| 4 | An online diagnosis technique for simultaneous measurement of the fundamental, second and third harmonics in one snapshot显示文摘A three-wavelength coherent-modulation-imaging(CMI)technique is proposed to simultaneously measure the fundamental,second and third harmonics of a laser driver in one snapshot.Laser beams at three wavelengths(1053 nm,526.5 nm and 351 nm)were simultaneously incident on a random phase plate to generate hybrid diffraction patterns,and a modified CMI algorithm was adopted to reconstruct the complex amplitude of each wavelength from one diffraction intensity frame.The validity of this proposed technique was verified using both numerical simulation and experimental analyses.Compared to commonly used measurement methods,this proposed method has several advantages,including a compact structure,convenient operation and high accuracy. | Xue Dong Xingchen Pan Cheng Liu Jianqiang Zhu | 2019 | High Power Laser Science and Engineering2019，7，3： | 1 |
| 5 | Chronic Nitrogen Fertilization Modulates Competitive Interactions Among Microbial Ammonia Oxidizers in a Loess Soil显示文摘Nitrogen(N) application may lead to niche segregation of soil ammonia-oxidizing archaea(AOA) and bacteria(AOB), thereby reducing the competitive interactions between AOA and AOB due to higher ammonium substrate availability. However, the adaptive mechanisms of AOA and AOB under N enrichment remain poorly understood. Stable isotope probing(SIP) microcosm incubation was employed to reveal community changes of active AOA and AOB in a loess soil from a field experiment growing potatoes that received no N(control, CK), low N(LN, 75 kg N ha^(-1)), and high N(HN, 375 kg N ha^(-1)). The results showed that the soil potential nitrification rate(PNR) was measured by culturing of the soil samples from the field experiment. Soil PNR was significantly increased in HN by87.5% and 67.5% compared with CK and LN, respectively. Compared with CK, the^(13)C-amoA genes of soil AOA and AOB in HN had 2.58 × 10~4 and 1.55 × 10~6 copies, representing 1.6-and 16.2-fold increase respectively. It was indicated that AOB dominated soil ammonia oxidation. A phylogenetic analysis of the^(13)C-amoA gene showed that N application significantly increased the proportion of54 d9-like AOA up to 90% in HN, while the Nitrososphaera gargensis-like and Nitrososphaera viennensis-like AOA were inhibited and completely disappeared. Nitrogen application also resulted in the community shift of active AOB-dominant group from Nitrosospira briensis-like to Nitrosospira sp. TCH711-like. Our study provides compelling evidence for the emergence and maintenance of active nitrifying communities under the intensified N input to an agricultural ecosystem. | DONG Xingchen ZHANG Jian QIU Huizhen ZHANG He LUO Chaoyue DENG Delei SHEN Qirong JIA Zhongjun | 2019 | Pedosphere2019，29，1： | 0 |
| 6 | Current Effect of“4+7”Drug Centralized Volume Procurement and Suggestions for Future Improvement显示文摘Objective To explore the impact of the“4+7”city drug centralized procurement policy implemented from April 1st,2019 on China’s pharmaceutical market and the differences between this pilot scheme and the first volume procurement,so as to put forward some suggestions for this policy and improve the drug price formation mechanism.Methods The characteristics of the“4+7”volume procurement policy and its improvements were summarized through literature research,and the distribution of the winning enterprises in volume procurement was shown by the chart.Then the overall situation of pharmaceutical enterprises in China was analyzed.Results and Conclusion According to the main distribution of enterprises in the alliance region,we can see that the first round of bid-winning enterprises with 25 varieties are mainly distributed in the eastern coastal cities of Jiangsu,Zhejiang,Shandong,and Guangdong,which shows a trend of developing to provinces of Sichuan,Hubei,and Hunan.With the increase of volume procurement inland cities will be included in the future.This pilot scheme of volume procurement is a reform of the entire pharmaceutical industry.It has improved the market structure and promoted the transformation and upgrading of regional medicine representatives.The most important thing is to enable the public to better enjoy the benefits brought by the low-priced drugs.However,for some pharmaceutical enterprises and drug retail industry,it is a challenge.Therefore,it is necessary to improve the policy and strengthen market supervision and management. | Piao Huiling Wei Xingchen Wang Nan Wang Xing Zhou Yusheng Dong Li | 2020 | Asian Journal of Social Pharmacy2020，15，4： | 0 |
| 7 | FXR suppresses colorectal cancer by inhibiting the Wnt/β-catenin pathway via activation of TLE3显示文摘Colorectal cancer(CRC)is the third most common and lethal cancer worldwide.1 Farnesoid X receptor(FXR)is a regulator of bile acid(BA)homeostasis and its expression is inversely correlated with the incidence of CRC.2,3 Moreover,our recent study discovered that dietary factors and dysregulated Wnt signaling independently alter BA profiles,some of which antagonize intestinal FXR,such as Tauro-β-muricholic acid(T-βMCA)and deoxycholic acid(DCA). | Xingchen Dong Chunmiao Cai Ting Fu | 2023 | Genes & Diseases2023，10，3： | 0 |
| 8 | Stability analysis of tunnel under coal seam goaf:Numerical and physical modeling显示文摘The goaf formed by coal seam mining would dramatically reduce the strength and stiffness of the ground in and around the goaf,which is not conducive to tunnel excavation near the mined-out area.By establishing the Finite differential method and Discrete element method coupling numerical analysis method and conducting similar model test,the influence of dip angle,thickness and distance of coal seam goaf on the stability of unsupported tunnel excavation is studied.The results show that when the tunnel under the goaf is exca-vated,the circumferential stress increment increases first and then decreases along the radial direction of the tunnel,the radial stress increment gradually decreases to zero along the radial direction of the tunnel,the displacement is approximately distributed in a trough shape,and the maximum displacement is at the top of the tunnel.The area of the stress loosening zone(SLZ)is negatively correlated with the dip angle and the distance of the goaf,and positively correlated with the thickness.The SLZ near the goaf is larger,and the peak value of the asymmetry is about 1.35.When the thickness of the mined-out area is 1.8–2.1 m,the SLZ and displacement around the tunnel increase sharply and then become stable.When the dip angle of the mined-out area is greater than 30°or the distance exceeds 1.3 times tunnel diameter(D),the asymmetry converges.The research results of this paper are of great importance to the design and construction of tunnel support and the formulation of excavation schemes. | Feng Huang Xiaoxiong Shi Chuangzhou Wu Guangfa Dong Xingchen Liu Aichen Zheng | 2023 | Underground Space2023，，4： | 0 |
| 9 | The Status Quo and Countermeasures of“4+7”Quantity Purchase in China显示文摘Objective To understand the effectiveness and problems of centralized drug procurement in China by analyzing the implementation of the“4+7”pilot work for centralized drug procurement in China.Methods The current situation and existing problems of drug procurement in China were analyzed through the literature research method.Results and Conclusion At present,good social benefits have been achieved for China’s drug procurement through pilot projects in several cities,but there are some serious problems.The proposed countermeasures will help to improve the procurement of pharmaceuticals in China. | Zhou Yusheng Wei Xingchen Piao Huiling Wang Nan Wang Xing Dong Li | 2020 | Asian Journal of Social Pharmacy2020，15，2： | 0 |
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