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Surface roughness measurement and analysis of mechanical parts based on digital holography

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Advances in Manufacturing 2016年第3期4卷 217-224页

作者： Wen-Jing Zhou Ke-Qin Peng ying-jie yu Department of Precision Mechanical Engineering ShanghaiUniversity Shanghai 200072 P. R. China

We measure the surface roughness of the mechanical parts based on digital holography. A digital off- axis hologram recording setup for reflective samples is built. Firstly, the height reconstruction error 2.3% of the setup is calibrated by using the quartz step height standard （VLSI- SHS-880QC）. Then, the standard scribed-line model and the grinding roughness specimen are selected as the test samples and their surface roughness are 0.095 6 jam and 0.025 3 jam, with errors 6.3%, 0.9%, respectively. The results are in good agreement with the given roughness parameters. At last, we also analyze the window effect of the filter on the roughness measurement value based on digital holography. In conclu- sion, the paper demonstrated effectively that the digital holography could provide the surface feature for the rough- ness measurement with high accuracy.

关键词： Digital holography - Digital off-axis hologram Roughness measurement Frequency filter window

In-situ stitching interferometric test system for large piano optics

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Advances in Manufacturing 2018年第2期6卷 195-203页

作者： Xin Wu ying-jie yu Ke-Bing Mou Wei-Rong Wang College of Mechanical Engineering Shanghai University of Engineering Science Shanghai 201620 People's Republic of China Department of Precision Mechanical Engineering Shanghai University Shanghai 200072 People's Republic of China Shanghai Machine Tool Works Ltd. Shanghai 200093 People's Republic of China

In-situ testing is an ideal technology for improv- ing the precision and efficiency of fabrication. We developed an in-situ subaperture stitching interferometric test system for large piano optics in the workshop environment with high precision and satisfactory repeatability. In this paper, we provide a brief account of this system and the principle ofin- situ subaperture stitching measurement. Several validation tests are presented, which demonstrate that the developed system is capable of realizing in-situ testing. The size of optical flats can be measured is up to 420 mm×780 mm, and repeatability is smaller than 0.03λ. The paper also dis- cusses the necessary requirements for a suitable workshop environment for ensuring that the tests are stable and reliable.

关键词： In-situ measurement Subaperture stitching Dynamic interferometry Large plano optics

Phase error correction for fringe projection profilometry by using constrained cubic spline

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Advances in Manufacturing 2014年第1期2卷 39-47页

作者： Jun-Zheng Peng Hang-Kong Ouyang Quan yu ying-jie yu Ke-Sheng Wang Department of Precision Mechanical Engineering ShanghaiUniversity Shanghai 200072 People's Republic of China Department of Production and Quality Engineering NorwegainUniversity of Science and Technology Trondheim Norway

In fringe projection profilometry, the nonlinear intensity response caused by the γ effect of a digital projector results in periodic phase error and therefore measurement error. Previous error correction methods are largely based on the calibration of single γ value. However, in practice, it is difficult to accurately model the full range of the intensity response with a one-parameter γ function. In this paper, a compensated intensity response curve is generated and fitted with the constrained cubic spline. With the compensated curve, the full range of the nonlinear intensity response can be corrected and the periodic phase errors can be removed significantly. Experimental results on a flat board confirm the average root mean square （RMS） of the phase error which can be reduced to at least 0.0049 rad.

关键词： Nonlinear intensity response Correction Constrained cubic

Interfacial behaviors between ZG13Cr9Mo1VNbN stainless steel and chromite sand

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Journal of Iron and Steel Research International 2025年第1期32卷 129-143页

作者： Shi-sen Li Xi-min Zang Ji-lin Chen jie Yang yu-an Jing Zhi-ying Wang Ling-zhong Kong School of Materials and Metallurgy University of Science and Technology LiaoningAnshan114051LiaoningChina School of Material Science and Engineering Shenyang University of TechnologyShenyang110870LiaoningChina Central Iron and Steel Research Institute Co. Ltd.Beijing100081China Xingtai Iron and Steel Co. Ltd.Xingtai054027HebeiChina

To elucidate the formation mechanisms of burn-on sand and metal penetration during sand casting,some laboratory experiments were carried out at different temperatures(1813,1833,1853,and 1873 K)and holding time(20,40,60,and 90 min)to simulate the interaction between ZG13Cr9Mo1VNbN stainless steel and chromite *** results demonstrate that the defects primarily consist of a mixture of the liquid phase,chromite,and *** main components of the liquid phase are SiO_(2),MnO,MgO,Cr_(2)O_(3),FeO,and Al_(2)O_(3),and the formation of Cr_(2)O_(3)through interfacial redox reactions has been *** presence of a liquid phase plays a pivotal role in influencing burn-on sand and metal *** reactions are prioritized,with burn-on sand maintaining a predominant *** the liquid phase quantity within the sand escalates,there is a corresponding incremental rise in the incidence of metal *** a minimal presence of the silicon element in steel can impact the liquid phase’s ***,the decomposition or dissolution of chromite sand is a significant factor in the development of burn-on sand and metal ***,a thorough investigation into the conditions and contributing factors of this phenomenon is essential for its effective management and mitigation.

关键词： Heat-resistant steel Chromite sand Interfacial reaction Burn-on sand Metal penetration Temperature Holding time

Reversible Li plating regulation on graphite anode through a barium sulfate nanofibers-based dielectric separator for fast charging and high-safety lithium-ion battery

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Journal of Energy Chemistry 2025年第2期101卷 511-523页

作者： Yaxin Zhang Long Cheng ying-jie Zhu Jin Wu Han-Ping yu Sida Xie Dandan Li Zhaohui Wang Heng Li State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences College of Materials Science and Engineering Hunan University Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Poor Li plating reversibility and high thermal runaway risks are key challenges for fast charging lithiumion batteries with graphite ***,a dielectric and fire-resistant separator based on hybrid nanofibers of barium sulfate（BS） and bacterial cellulose（BC） is developed to synchronously enhance the battery's fast charging and thermal-safety *** regulation mechanism of the dielectric BS/BC separator in enhancing the Li+ion transport and Li plating reversibility is revealed.（1） The Max-Wagner polarization electric field of the dielectric BS/BC separator can accelerate the desolvation of solvated Li+ions,enhancing their transport kinetics.（2） Moreover,due to the charge balancing effect,the dielectric BS/BC separator homogenizes the electric field/Li+ion flux at the graphite anode-separator interface,facilitating uniform Li plating and suppressing Li dendrite ***,the fast-charge graphite anode with the BS/BC separator shows higher Coulombic efficiency（99.0% vs.96.9%） and longer cycling lifespan（100 cycles vs.59 cycles） than that with the polypropylene（PP） separator in the constantlithiation cycling test at 2 mA *** high-loading LiFePO4(15.5 mg cm-2)//graphite(7.5 mg cm-2) full cell with the BS/BC separator exhibits excellent fast charging performance,retaining 70% of its capacity after 500 cycles at a high rate of 2C,which is significantly better than that of the cell with the PP separator（retaining only 27% of its capacity after 500 cycles）.More importantly,the thermally stable BS/BC separator effectively elevates the critical temperature and reduces the heat release rate during thermal runaway,thereby significantly enhancing the battery's safety.

关键词： Fast charging Graphite anode Ion transport Lithium-ion battery Separator

Effects of upstream tirofiban versus downstream tirofiban on myocardial damage and 180-day clinical outcomes in high-risk acute coronary syndromes patients undergoing percutaneous coronary interventions

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Chinese Medical Journal 2009年第15期122卷 1732-1737页

作者： LIU Tao XIE ying ZHOU yu-jie LI yue-ping MA Han-ying GUO Yong-he LIU yu-yang ZHAO ying-xin SHI Dong-mei Department of Geriatric Cardiology Beijing Anzhen Hospital Affiliated to Capital Medical University Beijing 100029 China

Background For patients with moderate to high-risk acute coronary syndromes （ACS） who undergo early, invasive treatment strategies, current guidelines recommend the usage of glycoprotein （GP） lib/Ilia inhibitors as an upstream treatment for a coronary care unit or as an downstream provisional treatment for selected patients who are undergoing percutaneous coronary intervention （PCI）. The relative advantage of either strategy is unknown. The purpose of this study was to evaluate the effects of upstream tirofiban versus the effects of downstream tirofiban on myocardial damage and 180-day major adverse cardiovascular events （MACE） after PCI in high-risk non-ST-segment elevation ACS （NSTE-ACS） undergoing PCI. Methods From July 2006 to July 2007, 160 high-risk NSTE-ACS undergoing PCI were randomized to receive upstream （within 4-6 hours before coronary angiography） tirofiban or downstream （the guidewire crossing the lesion） tirofiban, to evaluate the extent of myocardial damage after PCI by quantitatively and qualitatively analyzing the value of cardiac troponin I （cTnl） as well as MB isoenzyme of creatine kinase （CK-MB） before and after PCI. The incidences of 24-hour, 3-day, 7-day, 30-day and 180-day MACE after PCI were followed up and the rates of bleeding complications and thrombocytopenia during tirofiban administration were recorded. Results The peak release and cumulative release of cTnl levels within 48 hours after PCI were significantly lower with upstream tirofiban than downstream tirofiban （0.45 vs 0.63 and 0.32 vs 0.43, respectively; P 〈0.05）. Post-procedural cTnl elevation within 48 hours was significantly less frequent among patients who received the upstream tirofiban than those who received the downstream tirofiban （66.3% vs 87.5%, P 〈0.05）. The peak and cumulative release of CK-MB levels as well as post-procedural CK-MB elevation within 48 hours after PCI were not significantly different between the two groups （16 vs 14,5 vs 3 and 26.3% vs 36.3%, respecti

关键词： tirofiban coronary syndrome, acute angioplasty, transluminal, percutaneous coronary

Hemispheric asymmetries and network dysfunctions in adolescent depression:A neuroimaging study using resting-state functional magnetic resonance imaging

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World Journal of Psychiatry 2025年第2期15卷 100-108页

作者： ying Xiong Ren-Qiang yu Xing-yu Wang Shun-Si Liang jie Ran Xiao Li Yi-Zhi Xu Department of Hematology Chongqing General HospitalChongqing UniversityChongqing 401147China Department of Radiology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Psychiatry The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Currently,adolescent depression is one of the most significant public health concerns,markedly influencing emotional,cognitive,and social *** advancements in distinguish the neurobiological substrates underlying depression,the intricate patterns of disrupted brain network connectivity in adolescents warrant further *** To elucidate the neural correlates of adolescent depression by examining brain network connectivity using resting-state functional magnetic resonance imaging(rs-fMRI).METHODS The study cohort comprised 74 depressed adolescents and 59 healthy controls aged 12 to 17 *** underwent rs-fMRI to evaluate functional connectivity within and across critical brain networks,including the visual,default mode network(DMN),dorsal attention,salience,somatomotor,and frontoparietal control *** Analyses revealed pronounced functional disparities within key neural circuits among adolescents with *** results demonstrated existence of hemispheric asymmetries characterized by enhanced activity in the left visual network,which contrasted the diminished activity in the right *** DMN facilitated increased activity within the left prefrontal cortex and reduced engagement in the right hemisphere,implicating disrupted self-referential and emotional processing ***,an overactive right dorsal attention network and a hypoactive salience network were identified,underscoring significant abnormalities in attentional and emotional regulation in adolescent *** The findings from this study underscore distinct neural connectivity disruptions in adolescent depression,underscoring the critical role of specific neurobiological markers for precise early diagnosis of adolescent *** observed functional asymmetries and network-specific deviations elucidate the complex neurobiological architecture of adolescent depression,supporting the development of targeted the

关键词： Adolescent depression Brain network connectivity Neuroimaging biomarkers Functional magnetic resonance imaging Default mode network Salience network Hemispheric asymmetry

Interplay between creeping fat and gut microbiota: A brand-new perspective on fecal microbiota transplantation in Crohn's disease

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World Journal of Gastroenterology 2025年第2期31卷 138-143页

作者： ying Wang jie Liu Department of Life Sciences and Medicine South District of Endoscopic CenterThe First Affiliated Hospital of University of Science and Technology of ChinaUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Gastroenterology The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believed to serve as a predictor for early clinical recurrence following surgical intervention in patients with ***,the incorporation of the mesentery during ileocolic resection for CD has been correlated with a decrease in surgical recurrence,indicating the significant role of MAT in the pathogenesis of *** numerous studies have indicated that dysbiosis of the gut microbiota is a critical factor in the development of CD,the functional implications of translocated microbiota within the MAT of CD patients remain *** manuscript commentary discusses a recent basic research conducted by Wu et *** their study,intestinal bacteria from individuals were transplanted into CD model mice,revealing that fecal microbiota trans-plantation(FMT)from healthy donors alleviated CD symptoms,whereas FMT from CD patients exacerbated these ***,FMT was found to affect intestinal permeability,barrier function,and the levels of proinflammatory factors and ***,these findings suggest that targeting MAT and CrF may hold therapeutic potential for patients with ***,the study did not evaluate the composition of the intestinal microbiota of the donors or the subsequent alterations in the gut ***,the gut microbiota plays a crucial role in the histopathology of CD,and thus,targeting MAT and CrF may represent a promising avenue for treatment in this patient population.

关键词： Crohn's disease Mesenteric adipose tissue Creeping fat Fecal microbiota transplantation Gut microbiota

Risk factors for biometry prediction error by Barrett Universal II intraocular lens formula in Chinese patients

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 74-78页

作者： Xu-Hao Chen ying Hong Xiang-Han Ke Si-Jia Song yu-jie Cen Chun Zhang Beijing Key Laboratory of Restoration of Damaged Ocular Nerve Department of OphthalmologyPeking University Third HospitalBeijing 100191China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina

AIM:To investigate the influence of postoperative intraocular lens(IOL)positions on the accuracy of cataract surgery and examine the predictive factors of postoperative biometry prediction errors using the Barrett Universal II(BUII)IOL formula for ***:The prospective study included patients who had undergone cataract surgery performed by a single surgeon from June 2020 to April *** collected data included the best-corrected visual acuity(BCVA),corneal curvature,preoperative and postoperative central anterior chamber depths(ACD),axial length(AXL),IOL power,and refractive *** formula was used to calculate the IOL *** mean absolute error(MAE)was calculated,and all the participants were divided into two groups *** t-tests were applied to compare the variables between *** regression analysis was used to analyze the influence of age,AXL,corneal curvature,and preoperative and postoperative ACD on ***:A total of 261 patients were *** 243(93.1%)and 18(6.9%)had postoperative MAE1 D,*** number of females was higher in patients with MAE>1 D(χ^(2)=3.833,P=0.039).The postoperative BCVA(logMAR)of patients with MAE>1 D was significantly worse(t=-2.448;P=0.025).After adjusting for gender in the logistic model,the risk of postoperative refractive errors was higher in patients with a shallow postoperative anterior chamber[odds ratio=0.346;95% confidence interval(CI):0.164,0.730,P=0.005].CONCLUSION:Risk factors for biometry prediction error after cataract surgery include the patient’s sex and postoperative *** with a shallow postoperative anterior chamber are prone to have refractive errors.

关键词： intraocular lens power calculation gender anterior chamber depth biometry prediction error