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Journal of Materiomics 2021年第5期7卷 1094-1102页

作者： Shao Bo Chen Jia Yi yang shu ya wu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang University38 Zheda RoadHangzhou310027China

The variation of dielectric,ferroelectric and piezoelectric characteristics of BaZrO_(3)emodified(Ba_(0.85)Ca_(0.15))TiO_(3) ceramics,(1-x)(Ba_(0.85)Ca_(0.15))TiO_(3)-xBaZrO_(3),have been investigated together with the structure *** crystal structure at room-temperature varies from tetragonal to metrically cubic through orthorhombic and rhombohedral,and the morphotropic phase boundary(MPB)is determined around x=0.12 where the significantly enhanced dielectric,ferroelectric and piezoelectric characteristics are *** increasing x,the present ceramics indicate the crossover from normal to diffused and relaxor ferroelectric,and the evolution process is explored systematically.

关键词： Morphotropic phase boundary Diffused ferroelectric Relaxor ferroelectric

Greatly enhanced permittivity in BaTiO_(3)-epoxy dielectric composites with improved connectivity of ceramic phase

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Journal of Materiomics 2021年第1期7卷 1-7页

作者： Meng Cao Lei Li Wen Bin Hong shu ya wu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science&EngineeringZhejiang UniversityHangzhou310027China

BaTiO_(3)-epoxy dielectric composites were prepared by curing the liquid epoxy monomer that infiltrated into the partially-sintered BaTiO_(3)porous *** BaTiO_(3)volume fraction of the composites maintained around 58.6%with increasing the sintering temperature from 600℃to 1000°C,while the significant microstructure evolution,improved connectivity of BaTiO_(3)phase and dramatical increase in permittivity from 102 to 697 were *** permittivity and BaTiO_(3)volume fraction further increased to 2328 and 83.5%for the sintering temperature of 1250℃.The present composites had the permittivity 102 orders of magnitude higher than the 0-3 type ones,and the extraordinary results were mainly attributed to the improved connectivity of BaTiO_(3)phase that benefited from partial *** connectivity also had a significant effect on the temperature dependence of permittivity,and good combination of temperature-stable high permittivity,low dielectric loss and relatively low ceramic fraction could be obtained by regulating the connectivity of BaTiO_(3)ceramic phase.

关键词： Ceramic-polymer composite Connectivity High permittivity

A novel sol–gel route to synthesize(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ceramics with enhanced electrocaloric effect

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Journal of Advanced Dielectrics 2017年第2期7卷 28-35页

作者： Ting Chen shu ya wu Xiao Qiang Liu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 P.R.China

(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ultra-fine powders were synthesized by a novel sol–gel route,and the mechanism of the reaction was ***_(3),BaCO_(3),oxalate niobium and citric acid were used to initiate the sol–gel process,and ethylene glycol(EG)was added to further polymerize the cross-linking *** evolution of the(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) phase,the reaction process and the microstructures were investigated by X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared spectroscopy,DSC-TG and scanning electron *** synthesis temperature of the(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) powders reached as low as 1200℃,and the size and morphology of the powders were controlled by *** adjusting the calcination temperature,we obtained(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) powders with uniform sizes of 20 nm to 500 ***,dense(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ceramics were successfully prepared using these ultrafine ***,an enhanced electrocaloric effect(ECE)value of 0.35℃ was obtained at 100 kV/cm.

关键词： Sol–gel process (Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ultrafine powders electrocaloric effect

Room-temperature-densified H_(3)BO_(3) microwave dielectric ceramics with ultra-low permittivity and ultra-high Qf value

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Journal of Materiomics 2020年第2期6卷 233-239页

作者： Wen Bin Hong Lei Li Han yan shu ya wu Hang Sheng yang Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China

With the rapid development of mobile communication technology towards 5G and 6G,the microwave dielectric materials with ultra-low permittivity and ultra-high Qf value are urgently ***,the excellent microwave dielectric properties are reported in H3BO3 ceramics with the molecular crystal structure,whose permittivity(2.84)and density(1.46 g/cm^(3))are record-low among the low-loss *** ultra-high Qf value of 146,000 GHz(or the ultra-low dielectric loss of 1.03×10^(-4) at 15 GHz)is also ***,the H_(3)BO_(3) ceramics can be densified at room temperature by a simple cold sintering process in a short time of 10 min,and this brings many advantages for the integration with microwave *** large molecule volume originating from the molecular crystal structure and the low dielectric polarizabilities of H^(+) and B^(3+) are responsible for the ultra-low permittivity of H_(3)BO_(3) ceramics,and more microwave dielectric materials with ultra-low permittivity and ultra-high Qf value are expected to be explored in the molecular crystals.

关键词： Boric acid Microwave dielectric ceramics Room-temperature cold sintering Ultra-low permittivity

Study on the flow field uniformity of hydro-floating ship lift combined type hydraulic-driven system based on the residual energy theory

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Journal of Hydrodynamics 2022年第6期34卷 1156-1161页

作者： Bo wu ya-an Hu shu Xue State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing210029China Key Laboratory of Transport Technology in Navigation Building Construction Nanjing Hydraulic Research InstituteNanjing210029China

The hydro-floating ship lift originally invented in China is a major innovation in the field of navigation *** shaft water levels synchronization of its unique hydraulic-driven system plays a crucial role in reducing the torque of the synchronous shafts and ensuring the safety and stability operation of the ship *** study aims to investigate the muti-shaft water level synchronization and the flow velocity uniformity of the combined type hydraulic-driven *** on the theory of residual energy,a new index m2 proposed in this study is more suitable for evaluating the flow velocity uniformity of the combined hydraulic-driven ***,the critical value of m2=75 is calculated via the results of the scaled physical mode test as the threshold of water flow uniformity,and it provides a basis for determining the reasonable height of the pressure stabilizing chamber.

关键词： Hydro-floating ship lift water levels synchronism residual energy velocity distribution uniformity coefficient

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu yantong Li Meng-Xiang wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang ya Cheng Hai-Bo yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词：

nfluence of immune inflammation on androgen receptor expression in benign prostatic hyperplasia tissue

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Asian Journal of Andrology 2012年第2期14卷 316-319页

作者： Zong-Lin wu ya Yuan shu-Jie Xia Department of Urology Putuo District People's HospitalShanghai 200060China Department of Pathology Putuo District People's HospitalShanghai 200060China Department of Urology Shanghai First People's HospitalShanghai Jiao Tong UniversityShanghai 200080China

This study was designed to investigate the association between immune inflammation and androgen receptor （AR） expression in benign prostatic hyperplasia （BPH）. We retrospectively analyzed 105 prostatectomy specimens. An immune inflammation score for each specimen was defined by combining three immunohistochemical markers （CD4, CD8 and CD20）. The immunohistochemical markers were CD4 and CD8 for T lymphocytes, CD20 for B lymphocytes and AR antibody for the AR in BPH samples. Rates of CD4, CD8, CD20 and AR expression in BPH were 20 （19.0%）, 21 （20.0%）, 101 （96.2%） and 48 （45.7%）, respectively. Total prostate volume （TPV） was higher in the immune inflammation group than in the non-immune inflammation group （62.7 ml vs. 49.2 ml, t=-2.482, P〈0.05）. Patients in the immune inflammation group had a higher serum prostate-specific antigen （PSA） than those in the non-inflammation group （7.5 ng m1-1 vs. 5.4 ng m1-1, t=-2.771, P〈0.05）. Specifically, the immune inflammation group showed a higher rate of AR expression than the non-inflammation group （56.1% vs. 28.2%, χ2=7.665, P〈0.05）. Our study revealed a strong association between immune inflammation and TPV, serum PSA and AR expression in BPH tissue. Prostate hyperplasia caused by an immune inflammatory process may contribute to BPH progression over time. Therefore, the inflammatory response involved in BPH may be a prime therapeutic target.

关键词： androgen androgen receptor benign prostatic hyperplasia immunohistochemistry inflammation

高光谱预处理方法与多模型在分类判别中的对比研究

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光谱学与光谱分析 2025年第1期45卷 125-132页

作者：居雷于洁吴炎淼李丽卢天丁亚萍束茹欣上海烟草集团有限责任公司技术中心上海200082 上海大学化学系上海200444 上海数之微信息科技有限公司上海200444

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行... 详细信息

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行分类研究。采用Field Spec 3光谱辐射仪对293份不同部位的茄科植物粉末样本进行高光谱采样,采用S-G平滑以及一阶导数和二阶导数的方法对数据进行预处理,用于信息增强和去除噪声,并通过偏最小二乘法对数据进行降维,以减少冗余特征。基于降维数据,采样支持向量机、逻辑回归、K近邻、决策树、随机森林和梯度提升决策树这六种机器学习算法建立分类模型。结果显示,在分类任务中,经过一阶导数处理后,支持向量机模型最佳,在训练集和测试集上分别实现了100.0%和84.7%的准确率。经网格参数优化后确定最优参数为:最大深度不限制,最小样本分割数为4,估计器数量为200。参数优化后五折交叉验证准确率为88.1%,训练集准确率为100%,测试集准确率为86.4%。研究结果表明,预处理方法结合降维方法能够增强数据信息使得分类模型能够更好地捕捉茄科植物样本的特征。该研究对于快速、准确、无损地区分茄科植物的部位具有重要意义。

关键词：高光谱部位分类机器学习

Blockchain-based multi-hop permission delegation scheme with controllable delegation depth for electronic health record sharing

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High-Confidence Computing 2022年第4期2卷 14-22页

作者： ya Gao Aiqing Zhang shu wu Jindou Chen School of Physics and Electronic Information Anhui Normal UnivresityWuhu 241002China Anhui Provincial Engineering Laboratory on Information Fusion and Control of Intelligent Rabot Wuhu 241002China

Permission delegation has become a new way for data sharing by delegating the authorized permission to other users.A flexible authorization model with strict access control policies is promising for electronic health record(EHR)sharing with *** this paper,a blockchain-based multi-hop permission delegation scheme with controllable delegation depth for EHR sharing has been *** use the interplanetary file system(IPFS)for storing the original *** contracts and proxy re-encryption technology are implemented for permission *** order to ensure data security,we use attribute-based encryption to provide fine-grained access ***,blockchain is used to achieve traceability and *** deploy smart contracts so that the delegation depth can be set by *** analysis of the proposed protocol shows that our solution meets the designed ***,we evaluate the proposed algorithm and implement the scheme on the Ethereum test *** scheme outperforms the competition in terms of performance,according to the results of our experiments.

关键词： Blockchain Data security Permission delegation Access control Smart contract

Synthesis and Crystal Structure of 2-Amino-5,6-dihydro-4-(3,4-dimethoxyphenyl)-4H-benzo[h]chromene-3-carbonitrile

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Chinese Journal of Structural Chemistry 2006年第7期25卷 775-778页

作者： ZHUANG Qi-ya wu Nan SHI Da-Qing TU shu-Jiang Department of Chemistry Xuzhou Normal University Xuzhou 221116 China Key Laboratory of Biotechnology on Medical Plants of Jiangsu Province Xuzhou 221116 China

The title compound 2-amino-5,6-dihydro-4-（3,4-dimethoxyphenyl）-4H-benzo[h]- chromene-3-carbonitrile （C22H20N2O3, Mr = 360.40） was obtained by the reaction of 2-（3,4-dimeth- oxybenzylidene）-1-tetralone and malononitrile in DMF in the presence of KF-montmorillonite. Its structure was confirmed by IR and ^1H NMR spectra. The crystal is of monoclinic, space group C2/c with a = 24.101（6）, b = 9.146（2）, c = 17.238（3） ,A, β= 95.92（2）°, Z = 8, V= 3779.4（14） ,A^3, Dc = 1.267 g/cm^3, μ（MoKa） = 0.085 mm^-1, F（000） = 1520, R = 0.0409 and wR = 0.0981 for 2043 observed reflections （I 〉 2σ（I））.

关键词： KF-montmorillonite 2-aminochromene crystal structure synthesis