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Asymmetric transfer hydrogenation of ketones catalyzed by nickel complex with new PNO-type ligands

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Chinese Chemical Letters 2012年第5期23卷 533-536页

作者： zhen rong dong Yan Yun Li Shen Luan Yu Guo Song Sun Jing Xing Gao State Key Laboratory for Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Guangxi Research Institute of Chemical Industry Nanning 530001China

The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl_3,and fully characterized by IR,NMR and EIMS *** ligands were employed with a simple Ni complex Ni（PPh_s）_2Cl_2 in situ as catalytic systems for asymmetric transfer hydrogenation of ketones,and the corresponding optical alcohols were obtained with up to 84%ee under mild conditions.

关键词： Nickel complex NPO-type ligand Asymmetric transfer hydrogenation Ketones

Synthesis of novel chiral N,P-containing multidentate ligands and their applications in asymmetric transfer hydrogenation

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Chinese Chemical Letters 2011年第11期22卷 1269-1272页

作者： Shen Luan Yu Yan Yun Li zhen rong dong Juan Ni Zhang Qi Li Jing Xing Gao State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Laboratory for Green ChemicalProductions of Alcohols-Ethers-Esters and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Novel chiral PN_4-type multidentate aminophosphine ligands have been successfully synthesized by Schiff-base condensation of bis（o-formylphenyl）phenylphosphane and various chiral *** structures were fully characterized by IR,EI-MS and *** catalytic systems,prepared in situ from the multidentate ligands and iridium（I） complexes,showed high activity in asymmetric transfer hydrogenation of propiophenone in 2-propanol solution,leading to corresponding optical alcohol with up to 75%ee.

关键词： Chiral multidentate aminophosphine ligand Iridium complex Propiophenone Asymmetric transfer hydrogenation

Fusion of Spiral Convolution-LSTM for Intrusion Detection Modeling

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Computers, Materials & Continua 2024年第5期79卷 2315-2329页

作者： Fei Wang zhen dong School of Cyberspace Security Gansu University of Political Science and LawLanzhou73000China

Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection *** dataset is first preprocessed using solo thermal encoding and normalization *** the spiral convolution-Long Short-Term Memory Network model is constructed,which consists of spiral convolution,a two-layer long short-term memory network,and a *** is shown through experiments that the model is characterized by high accuracy,small model computation,and fast convergence speed relative to previous deep learning *** model uses a new neural network to achieve fast and accurate network traffic intrusion *** model in this paper achieves 0.9706 and 0.8432 accuracy rates on the NSL-KDD dataset and the UNSWNB-15 dataset under five classifications and ten classes,respectively.

关键词： Intrusion detection deep learning spiral convolution long and short term memory networks 1D-spiral convolution

Evaluation of Auto-Ignition Characteristics of Diesel Surrogate Fuels with the Same Derived Cetane Numbers at Changed Thermodynamic Environments

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Journal of Thermal Science 2024年第4期33卷 1590-1606页

作者： ZHANG Cong GUAN Yuanhang HUANG zhen HAN dong Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China College of Smart Energy Shanghai Jiao Tong UniversityShanghai200240China Shanghai Non-carbon Energy Conversion and Utilization Institute Shanghai200240China

The ignition tendency of diesel fuels is highly sensitive to ambient conditions and fuel *** this study,the ignition characteristics of different diesel surrogate fuels with the same derived cetane numbers(DCN)were measured and compared in varied thermodynamic and oxidizing *** combustion pressures,heat release rates,ignition delays,and combustion delays of the test fuels were *** experimental results showed that the diesel surrogate fuels with the same DCNs exhibit similar ignition propensity at standard DCN test ***,for the test conditions of high cetane fuels,high ambient temperatures,and suficient oxygen concentrations,surrogate fuels with the same DCN have similar ignition behaviors,and using the DCN to evaluate fuel ignition tendency is ***,for the test conditions of low cetane fuels,low ambient temperatures,and reduced oxygen concentrations,different ignition behaviors are observed for the surrogate fuels with the same DCN,so at these conditions using DCN as the evaluation index for fuel ignition tendency may lead to higher uncertainty.

关键词： diesel fuels surrogate fuels derived cetane numbers constant volume combustion chamber

Practical effect of different teaching modes in teaching gastrointestinal surgery nursing

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 166-172页

作者： Xiao-Juan rong zhen Ning Department of Nursing Medical College in Jiangxi University of TechnologyNanchang 330098Jiangxi ProvinceChina

BACKGROUND With the continuous development and progress of medical technology,the position of surgical nursing in the field of clinical medicine is becoming in-creasingly *** an important branch of the surgical field,the nursing requirements and difficulty of gastrointestinal surgery are also *** order to improve the teaching quality of nursing care in gastrointestinal surgery,many educators and researchers are actively exploring new teaching *** them,the teaching method case-based learning(CBL),scene-simulated learning(SSL),task-based learning(TBL),combining self-evaluation and training mode is considered as an effective *** method aims to help students to better master knowledge and skills and improve their comprehensive quality by cultivating their self-evaluation *** To explore the practical effect of CBL-SSL-TBL combined with training mode and student self-assessment in nursing teaching of gastrointestinal *** Seventy-one nursing interns in our hospital from December 2020 to December 2021 were *** to different teaching modes,they were divided into observation group CBL-SSL-TBL combined with training mode combined with student self-assessment and control group(conventional teaching mode),of which 36 were in observation group and 35 were in control *** results of operational skills,theoretical knowledge,nursing students'satisfaction,learning effectiveness questionnaire and teaching effect were compared between the two *** Compared between the two groups,the operational skills and theoretical knowledge scores of the observation group were higher than those of the control group,and the difference was statistically significant(P<0.05).Compared between the two groups,the total satisfaction ratio of the observation group was higher than that of the control group,the difference was statistically significant(P<0.05).Compared between the two groups,the observation group was lower tha

关键词： Gastrointestinal surgery Nursing teaching Teaching model Practical effect Learning ability

Double-stranded DNA-nucleic acid dye complex-sensitized biocatalytic photosynthesis:Base pairing-switched regeneration of nicotinamide cofactor

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Journal of Energy Chemistry 2024年第7期94卷 618-624页

作者： zhen dong Yanying Wang Dan Li Peng Wu College of Chemistry Sichuan UniversityChengdu 610064SichuanChina Analytical&Testing Centre State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064SichuanChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanChina

Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable *** is thus important to develop light antennas with both good light har-vesting and efficient electron ***,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for *** SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic *** SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved.

关键词： Photosynthesis dsDNA SYBRGreenI TICT 2-phenylpropanol

Biomimetic design of highly flexible metal oxide nanofibrous membranes with exceptional mechanical performance for superior phosphopeptide enrichment

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Nano Research 2024年第5期17卷 4270-4278页

作者： Xue Mao zhen-zhen Li dong-Lian Hao Wei-dong Han Gao-Peng Li Yao-Yu Wang Kun Zhang School of Textile Science and Engineering Key Laboratory of Functional Textile Material and Product(Ministry of Education)Xi’an Polytechnic UniversityXi’an 710048China Key Laboratory of Magnetic Molecules&Magnetic Information Materials of the Ministry of Education School of Chemistry&Material ScienceShanxi Normal UniversityTaiyuan 030031China Department of Clinical Laboratory The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004China Shanghai iProteome Biotechnology Co. LtdShanghai 201210China College of Chemistry&Materials Science Northwest UniversityXi'an 710127China

Developing free-standing and mechanical robust membrane materials capable of superior enrichment of phosphopeptides for analyzing and identifying the specific phosphoproteome of cancer cells is significant in understanding the molecular mechanisms of cancer development and exploring new therapeutic approaches,but still a significant challenge in materials *** this end,we firstly constructed highly flexible ZrTiO_(4) nanofibrous membranes(NFMs)with excellent mechanical stability through a cost-effective and scalable electrospinning and subsequent calcination ***,to further increase the enrichment capacity of the phosphopeptide,the biomimetic TiO_(2)@ZrTiO_(4) NFMs with root hair or leaf like branch microstructure are developed by the hydrothermal post-synthetic modification of ZrTiO_(4) NFMs through growing unfurling TiO_(2) nanosheets onto the ZrTiO_(4) ***,remarkable flexibility and mechanical stability enable the resulting TiO_(2)@ZrTiO_(4) NFMs excellent practicability,while the biomimetic microstructure allows it outstanding enrichment ability of the phosphopeptide and identification ability of the specific phosphoproteins in the digest of cervical cancer ***,6770 phosphopeptides can be enriched by TiO_(2)@ZrTiO_(4) NFMs(2205 corresponding phosphoproteins can be identified),and the value is much higher than that of ZrTiO_(4) NFMs(6399 phosphopeptides and 2132 identified phosphoproteins)and commercial high-performance TiO_(2) particles(4525 phosphopeptides and 1811 identified phosphoproteins).These results demonstrate the super ability of TiO_(2)@ZrTiO_(4) NFMs in phosphopeptide enrichment and great potential for exploring the pathogenesis of cancer.

关键词： inorganic nanofibers flexible ceramic nanofibrous membranes biomimetic materials exceptional mechanical performance flexibility

Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： WANG Lei dong Ying-hui HUA Chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility S-shaped utility concavification

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-Yi Yuan dong Bai zhen Wang Zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process