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Chinese Journal of Structural Chemistry 2020年第10期39卷 1841-1848,1744页

作者： CHEN zhao-hua GUO Cai-hua LU zhen-hua YANG Qin-Tian College of Food and Biological Engineering Jimei UniversityXiamenFujian 361021China

Combination of D-π-A stilbazolium-type dye DANP(DANP=trans-4-(4″-(N,N-diethylaminostyryl))-N-methyl-pyridinium)with zinc chloride results in a new hybrid(DANP-H)(ZnCl4)(1),and its structure was determined by single-crystal X-ray diffraction *** the hybrid,two independent DANP-H^2+cations exhibit two kinds of configurations,i.e.,conjugation-broken and conjugation-maintained fashions,and the X-aggregation mode of(DANP-H)^2+cations is driven by strong C–H…Cl hydrogen bonds and C–H…π***,blue-shift was observed in its adsorption spectrum,and unquenched red photoluminescence can be ***,dual stimuli-responsive performance and reversible photo/thermochromic behaviors appeared,which can be assigned to the electron transfer from Cl-3p/DANP-πtoπ*antibonding orbitals of the conjugation-maintained DANP.

关键词： stilbazolium-type dye zinc chloride X-aggregation photoluminescence photo/thermochromism

Evaluation of corneal cell growth on tissue engineering materials as artificial cornea scaffolds

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International Journal of Ophthalmology(English edition) 2013年第6期6卷 873-878页

作者： Hai-Yan Wang Rui-hua Wei Shao-zhen zhao Department of Ophthalmology Shijiazhuang No.1 Hospital Department of Ophthalmology Tianjin Medical UniversityEye Hospital

The keratoprosthesis(KPro;artificial cornea)is a special refractive device to replace human cornea by using heterogeneous forming materials for the implantation into the damaged eyes in order to obtain a certain *** main problems of artificial cornea are the biocompatibility and stability of the tissue particularly in penetrating *** current studies of tissue-engineered scaffold materials through comprising composites of natural and synthetic biopolymers together have developed a new way to artificial *** a wide agreement that the long-term stability of these devices would be greatly improved by the presence of cornea cells,modification of keratoprosthesis to support cornea cells remains *** of the studies on corneal substrate materials and surface modification of composites have tried to improve the growth and biocompatibility of cornea cells which can not only reduce the stimulus of heterogeneous materials,but also more importantly continuous and stable cornea cells can prevent the destruction of *** necrosis of stroma and spontaneous extrusion of the device,allow for maintenance of a precorneal tear layer,and play the role of ensuring a good optical surface and resisting bacterial *** a result,improvement in corneal cells has been the main aim of several recent investigations;some effort has focused on biomaterial for its well biological properties such as promoting the growth of cornea *** purpose of this review is to summary the growth status of the corneal cells after the implantation of several artificial corneas.

关键词： artificial cornea keratoprosthesis tissue-engineered scaffold corneal cells collagen fibrin amniotic membrane biomaterial

Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： Lu Tang zhen-hua Zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB25**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHB model,with a root-mean-square deviation of 0.0092 *** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

Determination of Flow Curve and Plastic Anisotropy of Medium-thick Metal Plate:Experiments and Inverse Analysis

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Journal of Iron and Steel Research International 2015年第6期22卷 506-512页

作者： Xin-cun ZhuaNG hua XIANG Tao WANG zhen zhao Tan LI Institute of Forming Technology and Equipment School of Materials Science and EngineeringShanghai Jiao Tong University

Sheet bulk metal forming is widely used for medium thick metal plate due to its convenience in the manu- facture of accurately finished 3D functional components. To obtain precise anisotropy and flow curve of metal plate is a prerequisite for correct simulation of sheet bulk metal forming processes. Inverse analysis of compression test was introduced here to evaluate the sensitivity of different flow curve models and geometric influence of compression test specimen. Besides, a methodology was proposed to compute plastic anisotropic coefficients of Hill quadratic yield cri- terion, which is based on the ratios of flow curves obtained by inverse analysis of compression tests using specimens cut in six directions on the medium-thick metal plate. The obtained flow curves and anisotropic coefficients were compared with those calculated from tensile tests. Flow curves based on inverse analysis of compression tests cover the curves of the tensile tests well, while the anisotropic coefficients are different, especially for the coefficient relat- ed to the RT45 direction. To estimate the effectiveness of the proposed method, the calculated material properties and those based on the traditional tensile tests were applied in a rim-hole process simulation. The simulation results based on the material properties from inverse analysis of compression tests accorded with the tested properties better.

关键词： inverse analysis anisotropic coefficient sheet bulk metal forming compression flow curve

An Overview of Structural Design,Analysis and Common Monitoring Technologies for Floating Platform and Flexible Cable and Riser

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China Ocean Engineering 2022年第4期36卷 511-531页

作者： WU Wen-hua zhao Yan GOU Ying LYU Bai-cheng LU Qing-zhen LU zhao-kuan YAN Jun Faculty of Vehicle Engineering and Mechanics State Key Laboratory of Structural Analysis of Industrial Equip-mentDalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315000China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China China National Offshore Oil Corporation(CNOOC)Research Institute Beijing 100027China

Offshore oil and gas development plays an important part in the global energy *** platforms and flexible pipes are the key equipments in the whole offshore oil and gas development *** of the randomness and uncertainty of wave and current loads in the ocean environment,the structural design and mechanical analysis of the marine equipment can be highly ***,this paper reviews the recent works of the theoretical model,numerical simulation,and experimental test in three research areas:hydrodynamic analysis of offshore platforms,structural mechanics analysis of flexible pipe and cable,and monitoring technology of offshore floating structures under marine *** analyzing their main research methods and key technical difficulties,this paper provides theoretical basis and technical support for the reliability engineering application of offshore platforms and flexible ***,China is relatively backward in the design of marine floating platform,the design,analysis and testing of flexible pipeline and cable,as well as the marine equipment prototype monitoring technology *** for breakthroughs at the earliest possible stage in the above fields,prime research should be focused on and strategic planning should be made to deal with“key areas and stranglehold problems”.It is of great significance for the development of China's deep-sea energy and resource development of independent technology and on time to achieve the“carbon peak”national strategic objectives.

关键词： review marine floating platform flexible pipeline and cable prototype monitoring

Metabolomic and transcriptomic analysis reveals the molecular mechanism by which blue light promotes lutein synthesis in strawberry

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Journal of Integrative Agriculture 2023年第6期22卷 1695-1703页

作者： CHEN Xiao-dong CAI Wei-jian XIA Jin YUAN hua-zhao WANG Qing-lian PANG Fu-hua zhao Mi-zhen Institute of Pomology Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic ImprovementNanjing 210000P.R.China

Carotenoids are an important component of the human diet, and fruit is a primary source of carotenoids. The synthesis and regulation of carotenoids in fruit are important contributors to the formation of fruit quality. In China, strawberry is one of the main seasonal fruits grown in the winter. Previous studies have shown that light has a significant effect on the metabolism of anthocyanins, sugars, and polyphenols in strawberry. However, the understanding of the role of light in regulating the metabolism of carotenoids in strawberry remains limited. This study investigated the effects of blue, red, yellow-green, and white light on carotenoid metabolism in *** light treatment promoted the synthesis of multiple carotenoids, including lutein, compared with the other three treatment groups. The RNA sequencing data revealed that blue light treatment promoted the expression of lycopene ε-cyclase(LCYE), and the transient overexpression of LCYE in strawberry fruit promoted lutein accumulation in strawberry. Overall, the results suggest that blue light can promote the synthesis of lutein in strawberry by inducing the expression of LCYE.

关键词： carotenoid LED light strawberry lutein

稀土化合物对MNNG致穿梭质粒pSP189突变的影响

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卫生毒理学杂志 1998年第3期12卷 138-140页

作者：崔明珍杨华赵素娟李申德北京市劳动卫生职业病防治研究所中国医学科学院肿瘤研究所细胞生物室

为探讨稀土抗诱变作用机理，本研究以穿梭质粒ｐＳＰ１８９，经具致癌作用的烷化剂甲基硝基亚硝基胍（ＭＮＮＧ）或ＭＮＮＧ加柠檬酸稀土同时处理后，转染猴肾ＶｅｒｏＥ６细胞，从细胞中回收的质粒转化大肠杆菌ＭＢＭ７０７０。结果表... 详细信息

为探讨稀土抗诱变作用机理，本研究以穿梭质粒ｐＳＰ１８９，经具致癌作用的烷化剂甲基硝基亚硝基胍（ＭＮＮＧ）或ＭＮＮＧ加柠檬酸稀土同时处理后，转染猴肾ＶｅｒｏＥ６细胞，从细胞中回收的质粒转化大肠杆菌ＭＢＭ７０７０。结果表明，ＭＮＮＧ浓度在１．５～６．０μｇ／ｍｌ范围，突变率明显的高于溶剂对照。稀土浓度分别为１０，２０及４０μｇ／ｍｌ与３μｇ／ｍｌＭＮＮＧ同时处理质粒，发现突变率分别为１５．２×１０－４、１０．０×１０－４及１２．７×１０－４，明显低于ＭＮＮＧ单独处理时的２５．１×１０－４，推测稀土可能阻断ＭＮＮＧ引起的Ｇ．Ｃ→Ａ．Ｔ转换，保护质粒ｐＳＰ１８９的靶基因ＳｕｐＦｔＲＮＡ免受损伤或影响某些基因表达。

关键词：稀土化合物穿梭质粒突变 MNNG

Time-domain training sequences design for MIMO OFDM channel estimation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 464-469页

作者： zhen LU Jian-hua GE Department of Electronic Engineering Shanghai Jiao Tong Universiry Shanghai 200240 China Department of Communications Engineering Xidian University Xi＇an 710071 China

This paper describes a Least Squares (LS) channel estimation scheme for MIMO OFDM systems based on time-domain training sequence. We first compute the minimum mean square error (MSE) of the LS channel estimation, and then derive the optimal criteria of the training sequence with respect to the minimum MSE. It is shown that optimal time-domain training sequence should satisfy two criteria. First, the autocorrelation of the sequence transmitted from the same antenna is an impulse function in a region longer than the channel maximum delay. Second, the cross-correlation between sequences transmitted from different antennas is zero in this region. Simulation results show that the estimator using optimal time-domain training sequences has better performance than that using optimal frequency training sequence at low signal-to-noise ratio (SNR). To reduce the training overhead, a suboptimal training sequence is also proposed. Comparing with optimal training sequence, it has low computation complexity and high transmission efficiency at the expense of little performance degradation.

关键词： MIMO OFDM Channel estimation Time-domain training sequence

PC-based frame synchronization method for byte-misaligned stream

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 23-28,34页

作者： CAI Yu-chen WANG zhen-hua ZHANG Guo-feng CHEN zhao-hui Software Department Beijing Institute of Control Engineering

As the traditional character-oriented frame synchronization methods are no longer applicable to the byte-misaligned stream, and the efficiency of the bit-oriented method is hardly acceptable, a character-oriented bit-shift stream frame synchronization （COBS-FS） method is presented. In order to measure the performance of the given method, a bit-oriented frame synchronization method, based on Knuth-Morris-Pratt （KMP-FS） algorithm, is used for comparison. It is proven in theory that the COBS-FS has a much lower cost in frame header searching. Experiment shows that the COBS-FS method is with better performance than the KMP-FS algorithm in both computational effort and execution time.

关键词： byte-misaligned stream frame synchronization sliding window method KMP

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期 337-349页

作者： Meiyun Xu Song Gu Fulong Chen Zhe zhao Peng Liu Daoben hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

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