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A novel ophthalmic viscosurgical devicefree phakic intraocular lens implantation makes myopic surgery safer

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Eye and Vision 2020年第1期7卷 171-179页

作者： An-Peng Pan Li-Jin Wen Xu Shao Kai-Jing Zhou Qin-Mei Wang Jia Qu A-Yong Yu The Eye Hospital of Wenzhou Medical University 270 Xueyuan West Road

Purpose:To assess the efficacy and safety of a novel ophthalmic viscosurgical device-free(OVD-free)method for posterior chamber phakic intraocular lens(PIOL)implantation in myopic ***:In this retrospective cohort study,the medical records of myopic eyes that underwent PIOL(Implantable Collamer Lens,ICL)implantation for myopia correction at the Eye Hospital of Wenzhou Medical University between May 2015 and March 2017 were reviewed.A total of 49 eyes with complete data that met follow up requirements(2 h,1 day,1 week,3 months postoperatively)were *** on the surgical techniques used,the eyes were divided into the OVD-free method group and the standard method *** clinical data,including intraocular pressure(IOP),corrected distance visual acuity(CDVA)and spherical equivalent(SE),at each follow-up were collected for *** cell loss and complications were also ***:Twenty-one eyes received the standard method,and 28 eyes received the OVD-free method.A rise in IOP>22 mmHg at 2 h was noted in 14 eyes(66.7%)in the standard group and none(0%)in the OVD-free group(p<0.001).The rise in IOP from baseline was significantly higher at 2 h in the standard group(10.5±5.2 mmHg vs.2.2±3.3 mmHg,difference:8.3,95%CI 5.8 to 10.8;p<0.001).There was a significant difference in the time course of LogMAR CDVA changes between the two groups(p=0.047).The LogMAR CDVA was significantly better in the OVD-free method group compared to the standard group at 1 day(−0.076,95%CI−0.134 to−0.018;p=0.012),1 week(−0.071,95%CI−0.135 to−0.007;p=0.03),but not at 3 months(−0.046,95%CI−0.107 to 0.015;p=0.134).There was no significant difference in the time course of SE changes between the two groups(p=0.471;p=0.705).In the OVD-free group,mean endothelial cell loss was 4.6%at 3 months(2522±281 vs.2407±226 cells/mm^(2),difference:-115,95%CI−295 to 65;p=0.187).No complications were reported in both groups except for the early IOP elevation in the standard

关键词： Phakic intraocular lens implantation Ophthalmic viscosurgical device-free Intraocular pressure Complications

Proca equation and vector field quantization in a rotating system

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Chinese Physics C 2021年第11期45卷 115-121页

作者： Tian Xu Yin Jiang Physics Department Beihang University37 Xueyuan RdBeijing 100191China

A strong background field drastically changes the vacuum structure and proper basis of a system in both classical and quantum mechanics,e.g.,the Landau levels in a background magnetic *** is true even for a rotating *** such a system,the usual set of plane-wave states would no longer be suitable as a starting point of *** and straightforwardly,in a rapidly and globally rotating system,it is better to reformulate the perturbation computation in *** this study,we completed the first step for the spin-1 field,which includes solving the Proca equation in the presence of a background rotation and completing its canonical *** show that because of the symmetry,the eigen states are actually the same as those of Maxwell equations in cylindrical *** propagator as well as the near-central approximation were obtained by assuming that the vorticity areas are very small in the relativistic QGP.

关键词： vector field quantization in rotating frame Proca equation

Microstructure and mechanical properties of Nb-Si alloys fabricated by spark plasma sintering

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Progress in Natural Science:Materials International 2013年第1期23卷 55-63页

作者： Wei Liu Yongming Fu Jiangbo Sha School of Materials Science and Engineering Beihang University37 Xueyuan Road

This paper deals with microstructural evolutions and mechanical properties of Nb-Si binaries containing dual-phase Nb/Nb5Si3 with Nb to Nb5Si3 fraction ratios of 90:10,80:20,70:30 and 50:50,prepared by spark plasma sintering(SPS).Dense Nb/Nb5Si3 samples with a relative density larger than 99.5% were obtained by SPS *** SPS samples consist of the Nb and Nb5Si3 phases with less than 3% fraction of NbO *** at room temperature,and compressive strength at 1150℃ and 1250 1C of the bulk SPS alloys increase monolithically by enhancing fraction of the stiffening Nb5Si3 *** example,0.2% yield strength,σ0.2,increases from 175 MPa to 420 MPa at 1150℃ and from 110 MPa to 280 MPa at 1250℃,when the Nb5Si3 fraction increases from 10% to 50%.It is interesting that the fracture toughness,KQ,of the bulk SPS samples seems not to be sensitive to phase *** treatment,however,plays a key role on the KQ as compared with that of the as-sintered state,at the corresponding Nb5Si3 fraction and considerably improves the KQ by about 100% for samples with the Nb5Si3 fractions of 10%-30%,and by about 50% for the sample with 50% Nb5Si3 fraction.

关键词： Nb-Si alloy Spark plasma sintering(SPS) Phase fraction Fracture toughness High-temperature strength

Additive manufacturing of magnesium matrix composites: Comprehensive review of recent progress and research perspectives

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Journal of Magnesium and Alloys 2023年第2期11卷 425-461页

作者： Chenghang Zhang Zhuo Li Jikui Zhang Haibo Tang Huaming Wang Ningbo Institute of Technology Beihang UniversityNingbo315800China National Engineering Laboratory of Additive Manufacturing for Large Metallic Components Beihang University37 Xueyuan RoadBeijingChina Research Institute for Frontier Science Beihang University37 Xueyuan RoadBeijingChina Research Center on Laser Direct Manufacturing for Large Critical Metallic Component Beihang University37 Xueyuan RoadBeijingChina

The magnesium matrix composites(MMCs) formed by introducing reinforcements to magnesium alloys overcome the limitations of the mechanical properties to a certain extent, presenting unique and excellent properties that any component does not have, such as high specific stiffness and specific strength, good dimensional stability, outstanding shock absorption performance, excellent electromagnetic shielding and hydrogen storage characteristics, etc. As an emerging manufacturing technology, additive manufacturing(AM) is based on the design of threedimensional(3D) data model to obtain 3D objects through layer-by-layer processing, which possesses the advantages of short manufacturing cycle, high material utilization rate, high degree of design freedom, excellent mechanical properties and the ability to fabricate complex structural components. Combining the high stiffness and high strength properties of MMCs and the technical advantages of AM forming complex structural parts with high performance, the prepared AM MMCs have huge potential advantages and broad application prospects in new high-tech industries such as automobile, aerospace, consumer electronics and biomedicine, etc. This paper reviews the research progress in the field of AM MMCs, mainly introduces the main AM technologies, including selective laser melting(SLM), electron beam selective melting(EBSM), laser engineered net shaping(LENS) and wire and arc additive manufacturing(WAAM). The formation mechanism and control methods of the typical defects including balling effect, porosity, poor fusion, loss of alloy elements and cracks produced during AM are discussed. The main challenges of AM MMCs are proposed from the aspects of composition design and the preparation of powder raw material. The relationship between the microstructure and mechanical properties, corrosion performance and biocompatibility of AM MMCs are elaborated in detail. The application potential of AM MMCs in various fields at present and in th

关键词： Magnesium matrix composites Additive manufacturing Defects Microstructure Properties

Recent research and development on forming for large magnesium alloy components with high mechanical properties

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Journal of Magnesium and Alloys 2023年第11期11卷 4054-4081页

作者： Zhimin Zhang Jianmin Yu Yong Xue Beibei Dong Xi Zhao Qiang Wang College of Materials Science and Engineering North University of China3 Xueyuan RoadTaiyuan 030051China

The lightweight of high-end equipment relies on high mechanical properties magnesium(Mg) alloy structural components, because it is the best way to improve equipment service performance and reduce energy consumption. This article summarizes the current progress and characteristics of large-scale high-performance Mg alloy components by analyzing the strengthening-toughening mechanisms, characteristics of plastic forming, and the preparation of large high mechanical properties forging blanks. Due to the lack of breakthroughs in the key technologies for forming large-scale Mg alloy components, their uniformity of mechanical properties and consistency are poor, the forming accuracy of components is low, and the production cost is high, which limit their engineering application and restrict the lightweight level of high-end equipment. In view of the above problems, the forming trends and research directions of large-scale and high mechanical properties Mg alloy components are proposed in this paper. It can provide help for the breakthrough of the key technology of large-scale Mg alloy components with high mechanical properties and expand the application of Mg alloy in high-end products.

关键词： Mg alloys Wrought Mg alloys components Plastic forming Large-scale Mg alloys components High mechanical properties

The evolution of microstructure and texture of AZ80 Mg alloy cup-shaped pieces processed by rotating backward extrusion

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Journal of Magnesium and Alloys 2021年第5期9卷 1694-1708页

作者： Xin Che Qiang Wang Beibei Dong Mu Meng Zhi Gao Kai Liu Jin Ma Fulai Yang Zhiming Zhang College of Materials Science and Engineering North University of China3 Xueyuan RoadTaiyuan 030051PR China

This study proposed an effective plastic deformation technique,rotating backward extrusion(RBE),for producing high performance AZ80 magnesium alloy cup-shaped *** RBE process was carried on the Gleeble-3500 test machine at 653 K,and the conventional backward extrusion(CBE)was also conducted for comparison.A detailed microstructure analysis was performed using the optical microscopy(OM)and electron back-scatter diffraction(EBSD).The results shown that the equivalent strain and deformation uniformity of the cup pieces could be substantially increased by the RBE process compared with the CBE ***,the RBE process could significantly improve the grain refining capacity and the proportion of dynamic recrystallization(DRX),of which the maximum reduction of grain size was 88.60%,and the maximum increase of DRX proportion was 55.30%in the cup *** main deformation mechanism of the RBE process was the discontinuous DRX(DDRX),while the continuous DRX(CDRX)was also occurred in the cup *** with the CBE sample,the texture of the cup bottom was weakened for the RBE *** microhardness value of the RBE sample was higher than that of the CBE sample,which can be attributed to the grain refinement strengthening.

关键词： Rotating backward extrusion AZ80 magnesium alloy Dynamic recrystallizaton Texture

GSTAR:an innovative software platform for processing space geodetic data at the observation level

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Satellite Navigation 2023年第3期4卷 122-141页

作者： Chuang Shi Shiwei Guo Lei Fan Shengfeng Gu Xinqi Fang Linghao Zhou Tao Zhang Zhen Li Min Li Wenwen Li Cheng Wang Yidong Lou Key Laboratory of Navigation and Communication Fusion Technology Ministry of Industry and Information Technology37 Xueyuan RoadBeijing 100191China School of Electronic and Information Engineering Beihang University37 Xueyuan RoadBeijing 100191China Research Institute for Frontier Science Beihang University37 Xueyuan RoadBeijing 100191China GNSS Research Center Wuhan University129 Luoyu RoadWuhan 430079China

To meet the demands for the data combination with multiple space geodetic techniques at the observation level,we developed a new software platform with high extensibility and computation efficiency,named space Geodetic SpatioTemporal data Analysis and Research software(GSTAR).Most of the modules in the GSTAR are coded in C++with object-oriented *** layered modular theory is adopted for the design of the software,and the antenna-based data architecture is proposed for users to construct personalized geodetic application scenarios *** initial performance of the GSTAR software is evaluated by processing the Global Navigation Satellite System(GNSS)data collected from 315 globally distributed stations over two and a half *** accuracy of GNSS-based geodetic products is evaluated by comparing them with those released by International GNSS Service(IGS)Analysis Centers(AC).Taking the products released by European Space Agency(ESA)as reference,the Three-Dimension(3D)Root-Mean-Squares(RMS)of the orbit differences are 2.7/6.7/3.3/7.7/21.0 cm and the STandard Deviations(STD)of the clock differences are 19/48/16/32/25 ps for Global Positioning System(GPS),GLObal NAvigation Satellite System(GLONASS),Galileo navigation satellite system(Galileo),BeiDou Navigation Satellite System(BDS),Medium Earth Orbit(MEO),and BDS Inclined Geo-Synchronous Orbit(IGSO)satellites,*** mean values of the X and Y components of the polar coordinate and the Length of Day(LOD)with respect to the International Earth Rotation and Reference Systems Service(IERS)14 C04 products are-17.6 microarc-second(μas),9.2μas,and 14.0μs/*** to the IGS daily solution,the RMSs of the site position differences in the north/east/up direction are 1.6/1.5/3.9,3.8/2.4/7.6,2.5/2.4/7.9 and 2.7/2.3/7.4 mm for GPS-only,GLONASS-only,Galileo-only,and BDS-only solution,*** RMSs of the differences of the tropospheric Zenith Path Delay(ZPD),the north gradients,and the east gradien

关键词： GSTAR GNSS BDS LEO Precise orbit determination Precise clock estimation Earth rotation parameter Tropospheric zenith path delay Geocenter motion Rapid data processing

Engineering customized nanovaccines for enhanced cancer immunotherapy

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Bioactive Materials 2024年第6期36卷 330-357页

作者： Jinyu Guo Changhua Liu Zhaoyang Qi Ting Qiu Jin Zhang Huanghao Yang Qingyuan Innovation Laboratory 1 Xueyuan RoadQuanzhou362801PR China College of Chemical Engineering Fuzhou University2 Xueyuan RoadFuzhou350108PR China MOE Key Laboratory for Analytical Science of Food Safety and Biology State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou University2 Xueyuan RoadFuzhou350108PR China

Nanovaccines have gathered significant attention for their potential to elicit tumor-specific immunological *** notable progress in tumor immunotherapy,nanovaccines still encounter considerable challenges such as low delivery efficiency,limited targeting ability,and suboptimal *** an aim of addressing these issues,engineering customized nanovaccines through modification or functionalization has emerged as a promising *** tailored nanovaccines not only enhance antigen presentation,but also effectively modulate immunosuppression within the tumor ***,they are distinguished by their diverse sizes,shapes,charges,structures,and unique physicochemical properties,along with targeting *** features of nanovaccines facilitate lymph node accumulation and activation/regulation of immune *** overview of bespoke nanovaccines underscores their potential in both prophylactic and therapeutic applications,offering insights into their future development and role in cancer immunotherapy.

关键词： Nanovaccines Customized structure Tailored-ligand Enhanced cancer immunotherapy Prophylactic and therapeutic applications

Structural and Mechanical Characterization ofAtrina Pectinata and Freshwater Mussel Shells

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Journal of Bionic Engineering 2015年第2期12卷 276-284页

作者： Jianlu Lv Yonggang Jiang Deyuan Zhang School of Mechanical Engineering and Automation Beihang University Xueyuan Road No. 37 Haidian District Beij'ing 1 00191 China International Research Institute for Multidisciplinary Science Beihang University Xueyuan Road No. 37 Haidian District Belling 100191 China

The microstructures ofAtrina pectinata and freshwater mussel shells are investigated by optical microscopy and scanning electron microscopy. The mechanical properties of these shells are characterized by nanoindentation and three-point bending tests. Results show that both shells possess a prismatic microstructure mainly composed of columnar crystals and an organic matrix. The fracture toughness of the prismatic structure of Atrina pectinata and freshwater mussel are approximately 1.15 MPa.m1/2 and 0.87 MPa.m1/2, respectively, while the fracture toughness of natural calcite is approximately 0.2 MPa.m1/2. Calculated results from indentations agree with those obtained from the three-point bending tests. The columnar crystal material shows excellent fracture toughness due to grain refinement. In addition, the organic matrix of the prismatic layer can arrest cracks, and thereby improves the fracture toughness.

关键词： shell prismatic fracture toughness organic matrix crack