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SYNTHESIS AND CHARACTERIZATION OF A NEW COMPOUND :K_6Ti_0.67Nb_15.33O_42

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Journal of Wuhan University of Technology(Materials Science) 1999年第1期14卷 16-18页

作者： FANG liang ZHANG hui QING Linqin WU BolinWuhan University of Technology Wuhan University of Technology China Res. Inst. of Advanced Mater. Wuhan Univ. of Tech. Wuhan 430070 China

A new compound K6Ti0.67Nb15.33O42 was prepared for the first time by solid state reaction in K2O-Ni2O3-Nb2O5 ternary system. The new compound was characterized by electron probe, X-ray powder diffraction and DTA. The result of X-ray powder diffraction shows that K6Ti0.67Nb15.33O42 crystallizes the hexagonal system with unit cell parameters a = 9. 1341(5) A ,c=12. 090(1)A . and space group P62/mcm(193 ).

关键词： K2O-Ni2O3-Nb2O5 system new com- pound powder diffraction data

Developing an evaluation model to support evidence-based decision-making on provincial vaccination program of Zhejiang province

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Asian Pacific Journal of Tropical Medicine 2023年第12期16卷 527-532页

作者： Fuxing Chen Linlin Ding hui liang Ying Wang Yu Hu Institute of Immunization and Prevention Zhejiang Center for Disease Control and PreventionHangzhouChina

Vaccines are considered as one of the most cost-effective interventions to improve the global public health by reducing mortality and morbidity[1].At an ever-increasing pace,new vaccines are being developed and licensed in China,driven by initiatives from both domestic and international vaccine *** vaccines are evaluated by Chinese Advisory Committee on Immunization,which makes decisions regarding the use of vaccines based on the epidemiological context in China.

关键词： companies China provincial

In Situ Elimination of Pores During Laser Powder Bed Fusion of Ti–6.5Al–3.5Mo–l.5Zr–0.3Si Titanium Alloy

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Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 439-452页

作者： Ling Zhang Wen-He Liao Ting-Ting Liu hui-liang Wei Chang-Chun Zhang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094.China

The printing quality of components manufactured using laser powder bed fusion(LPBF)generally depends on the presence of various defects such as massive ***,the efficient elimination of pores is an important factor in the production of a sound LPBF *** this study,the efficacy of two in situ laser remelting approaches to eliminating pores during the LPBF of a titanium alloy Ti–6.5 Al–3.5 Mo–l.5 Zr–0.3 Si(TC11)was assessed both experimentally and *** two remelting methods are surface remelting and layer-by-layer printing and remelting.A multi-track multi-layer phenomenological model was established to analyze the variation of pores with the temperature and velocity *** results showed that surface remelting with a high laser power,such as 180 W,can eff ectively eliminate pores within three deposited ***,such remelting could not reach defects in deeper ***-by-layer remelting with a 180 W laser could eff ectively eliminate the pores formed in the previous layer in real *** results obtained in this study can provide useful guidance for the in situ control of printing defects supported by real-time monitoring,feedback,and operating systems of an intelligent LPBF equipment.

关键词： Laser powder bed fusion Ti–6.5Al–3.5Mo–l.5Zr–0.3Si Pores Laser remelting

Knowledge,perceptions,and practice towards adverse events following immunization surveillance among vaccination workers in Zhejiang province,China

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Asian Pacific Journal of Tropical Medicine 2023年第3期16卷 102-109页

作者： Huakun Lv Xuejiao Pan Ying Wang hui liang Hu Yu Institute of Immunization and Prevention Zhejiang Center for Disease Control and PreventionHangzhouChina

Objective:To access the level of knowledge,perceptions,and practice towards adverse events following immunization(AEFI)surveillance among vaccination workers in Zhejiang province,***:This was a cross-sectional survey involving 768 vaccination *** were collected using self-administered questionnaires and analyzed by using SAS 9.3 ***,perceptions,and practice on AEFI surveillance were summarized using frequency *** mean±SD value was used as the cut-off for defining good(values≥mean)and poor(values

关键词： Adverse events following immunization Surveillance Knowledge Perception Practice

Studies on Rheological, Thermal, and Mechanical Properties of Polylactide/Methyl Methacrylate-Butadiene-Styrene Copolymer/Poly(propylene carbonate) Polyurethane Ternary Blends

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Chinese Journal of Polymer Science 2019年第12期37卷 1273-1282,I0007页

作者： Ji-Li Zhao Hong-Wei Pan hui-Li Yang Jun-Jia Bian hui-liang Zhang Ge Gao Li-Song Dong College of Chemistry Jilin UniversityChangchun 130012China Department of Science Beihua UniversityJilin 132013China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Zhejiang Zhongke Applied Chemistry Technology Co. Ltd.Hangzhou 310000China

Polylactide(PLA),methyl methacrylate-butadiene-styrene copolymer(MBS),and poly(propylene carbonate)polyurethane(PPCU)were blended and subjected to blown film *** rheological,mechanical,morphological,thermal,and crystalline properties of the PLA/MBS/PPCU ternary blends and the mechanical properties of the resulting films were *** of mechanical test showed that PPCU and MBS could synergistically toughen *** impact strength of 50/10/40 PLA/MBS/PPCU blend(74.7 k J/m^2)was about 7.5 times higher than that of the neat PLA(10.8 k J/m^2),and the elongation at break of 50/10/40 PLA/MBS/PPCU blend(276.5%)was higher by about 45 times that of PLA(6.2%).The tear strength of PLA/MBS/PPCU films was 20 k N/m higher than that of PLA,and the elongation at break(MD/TD)of 50/10/40 PLA/MBS/PPCU films was 271.1%/222.3%,whereas that of PLA was only 2.7%/3.0%.POM observations displayed that the density of spherulite nucleation increased and the size of crystalline particles decreased with the addition of *** increasing PPCU content from 5%to 20%,the density of spherulite nucleation increased and the size of crystalline particles decreased continuously,but the nucleation density of spherulites was slightly lowered with increasing PPCU content from 30%to 40%.The PLA/MBS/PPCU films exhibited excellent mechanical properties,which expanded the application range of these biodegradable films.

关键词： Biodegradable Polylactide Poly(propylene carbonate)polyurethane Methyl methacrylate-butadiene-styrene copolymer Films

Effect of particle size on the microstructure and thermal conductivity of Al/diamond composites prepared by spark plasma sintering

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Rare Metals 2009年第6期28卷 646-650页

作者： CHU Ke JIA Chengchang liang Xuebing CHEN hui GAO Wenji School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Spark plasma sintering （SPS） was used to fabricate Al/diamond composites. The influence of diamond particle size on the microstructure and thermal conductivity （TC） of composites was investigated by combining experimental results with model prediction. The results show that both composites with 40 pan particles and 70 μm particles exhibit high density and good TC, and the composite with 70 μm particles indicates an excellent TC of 325 W.m^-1.K^-1. Their TCs lay between the theoretical estimated bounds. In contrast, the composite with 100 lain particles demonstrates low density as well as poor TC due to its high porosity and weak interfacial bonding. Its TC is even considerably less than the lower bound of the predicted value. Using larger diamond particles can further enhance thermal conductive performance only based on the premise that highly dense composites of strong interfacial bonding can be obtained.

关键词： metal matrix composites thermal properties sintering particle size

Pulse-shaping method for real-time neutron/gamma discrimination at low sampling rates

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Nuclear Science and Techniques 2023年第11期34卷 51-63页

作者： Jia‑Xin Li hui‑liang Hou Yue‑Feng Huang Mao‑Song Cheng Zhi‑Min Dai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The Na I:Tl scintillator is an innovative material for dual-gamma-ray and neutron detection with a low ^(6)Li *** achieve real-time n/γ discrimination,a zero-crossing time comparison algorithm based on trapezoidal pulse shaping was *** algorithm can operate efficiently at low sampling rates and was implemented on a single-probe portable digital n/γ discriminator based on a field-programmable gate *** discriminator and Na I:Tl,^(6)Li detector were tested in a neutron-gamma mixed field produced by an ^(241)Am-Be neutron source to evaluate the performance of the *** figure of merits was measured as 2.88 at a sampling rate of 50 MHz,indicating that the discriminator with its embedded algorithm has a promising n/γ discrimination *** discrimination at sampling rates of 40 and 25 MHz demonstrates that the capability of this method is not limited by low sampling rates.

关键词： FPGA NaI:Tl ^(6)Li Real time Neutron/gamma discrimination Pulse shaping

质子入射In靶激发L系特征X射线的角分布研究

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原子与分子物理学报 2025年第2期42卷 98-104页

作者：柳钰王兴徐忠锋周贤明程锐张小安梁昌慧咸阳师范学院与中国科学院近代物理研究所联合共建离子束与光物理实验室咸阳712000 西安交通大学物理学院西安710049 中国科学院近代物理研究所兰州730000

本论文实验测量并分析了发射角以10°为间隔,125°-155°范围内,入射能量为250 keV的质子束激发In靶产生的特征L系X射线谱,根据实验测得能谱结果,综合考虑探测器的探测效率后,计算了不同探测角度下特征X射线的相对强度比L_(ι)/L_(γ1)... 详细信息

本论文实验测量并分析了发射角以10°为间隔,125°-155°范围内,入射能量为250 keV的质子束激发In靶产生的特征L系X射线谱,根据实验测得能谱结果,综合考虑探测器的探测效率后,计算了不同探测角度下特征X射线的相对强度比L_(ι)/L_(γ1);由相对强度比L_(ι)/L_(γ1)与二阶勒让德函数P_(2)(cosθ)之间的函数关系,发现特征X射线Lι在被测能量下呈各向异性发射,推得Lι特征X射线的各向异性参数β为-0.179±0.011,进而得到In靶L_(3)亚壳层的定向度A_(20)为-0.422±0.025,实验结果与理论预测一致.根据PWBA(Plane wave born approximation)模型和ECPSSR(Energy-loss coulomb-repulsion perturbed-stationary-state relativistic)模型,计算了250 keV质子入射下,In靶L亚壳层电离截面σ及Coster-Kronig跃迁矫正因子κ,在根据各向异性参数计算L_(3)亚壳层定向度的过程中考虑了Coster-Kronig跃迁的作用.分析认为本实验碰撞速度下,通过电子转移方式产生空穴的截面比直接电离小的多,所以没有对L_(3)亚壳层定向度进行电子转移因素的修正.

关键词：碰撞电离特征X射线角分布各向异性

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SYNTHESIS AND CRYSTAL STRUCTURE OF A NEW COMPOUND Sr_6Sn_2Nb_8O_30

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Journal of Wuhan University of Technology(Materials Science) 1999年第2期14卷 35-39页

作者： FANG liang ZHANG hui WU Bolin YUAN Runzhang Wuhan University of Technology Wuhan University of Technology China State Key Lab. Adv. Tech. Mater. S. Wuhan Univ. of Tech. Wuhan 430070 China

A new compound Sr6Sn2Nb8O30 was found in the ternary system of SrO-SnO2-Nb2O5. The transparent colorless crystal with needle-like shape can be grown by flux method. The crystal structure of new compound was determined by X-ray diffraction, and its belongs to tungsten bronze structure. Sr6Sn2Nb8O30 crystallizes in orthorhombic system with unit cell parameters a= 17. 579 (DA,6= 17. 509(DA,c=7. 7880(5)A,Z = 4 and space group Cmm2.

关键词： Sr_6Sn_2Nb_8O_30 system new compound tungsten bronze structure