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BRANCHING GENERATION DURING THE FREE RADICAL COPOLYMERIZATION OF p-VINYL BENZENE SULFONYL CHLORIDE WITH STYRENE

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Chinese Journal of Polymer Science 2013年第10期31卷 1404-1414页

作者： cui-ping li Rong Huang Jia-qiang Wang Zan liu Department of Applied Chemistry Key Laboratory of Medicinal Chemistry for Natural Resource College of Chemistry Science and Engineering Yunnan University Kunming Cable Co. Ltd

The branching generation during the free radical copolymerization of chain transfer monomer p-vinyl benzene sulfonyl chloride （VBSC） with styrene was investigated by a simple mathematic model. Chain transfer constant of VBSC was determined to be around 0.3 by fitting the 1H-NMR monitored experimental results with a mathematic model. According to the theoretical analysis, the obtained poIy（VBSC） and its copolymers were substantiated to have a grafting-like main chain with residual pendent sulfonyl chloride groups after consuming most of the vinyl groups. The copolymerization results of VBSC with styrene at varied feed ratios demonstrated that conversion of sulfonyl chloride groups was lower than that of the monomer, which was in agreement with the theoretical results. The glass transition temperature, number average molecular weight and distribution of those obtained polymers were primarily investigated. Comparing with other chain transfer monomers, VBSC has a chain transfer constant much closer to unity therefore a more branched polymer is expected. Additionally, the branched polystyrene with residual sulfonyl chloride groups is hopefully to be further used as ATRP macro- initiators or reactive intermediates to synthesize functional polymers with complex structure.

关键词： Branched polystyrene Chain transfer constant Chain transfer monomer p-Vinyl benzene sulfonyl chloride Radical polymerization.

Dynamic Behavior of Entanglement Between Two Spatially Separated Atoms in Two Dissipative and Driven Cavity Fields

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Communications in Theoretical Physics 2009年第3期51卷 509-513页

作者： cui Hui-ping li Jian liU Jin li Jun-Gang Department of Physics School of Science Beijing Institute of Technology Beijing 100081 China

We consider two two-level atoms, interacting with two independent dissipative cavities, each of which is driven by an external source. The two cavity fields are both initially prepared in the coherent states, and the two two-level atoms are initially prepared in the singlet state ｜ψ^-〉 =（｜eg〉 - ｜ge〉） / √2. We investigate the influence of the damping constant n, the intensity of the external sources F, and the relative difference of the atomic couplings r on the entanglement between the two atoms. In the dispersive approximation, we find that the entanglement between the two atoms decreases with the time evolution, and the decreasing rate of entanglement depends on the values of F/k, k/ω, and r. For the given small values of F/k and k/ω, on the one hand, the increasing of r favors entanglement decreasing of the atomic system, on the other hand, when r → 1 the entanglement decreasing becomes slower. With the increasing of the value of k/ω, the influence of r on the decreasing rate of entanglement becomes smaller, and gradually disappears for the big value of k/ω.

关键词： entanglement dissipation driven field

Partial Label Learning via Conditional-Label-Aware Disambiguation

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Journal of Computer Science & Technology 2021年第3期36卷 590-605页

作者： Peng Ni Su-Yun Zhao Zhi-Gang Dai Hong Chen cui-ping li Key Laboratory of Data Engineering and Knowledge Engineering(Renmin University of China) Ministry of Education Beijing 100087China School of Information Renmin University of ChinaBeijing 100087China

Partial label learning is a weakly supervised learning framework in which each instance is associated with multiple candidate labels,among which only one is the ground-truth *** paper proposes a unified formulation that employs proper label constraints for training models while simultaneously performing *** existing partial label learning approaches that only leverage similarities in the feature space without utilizing label constraints,our pseudo-labeling process leverages similarities and differences in the feature space using the same candidate label constraints and then disambiguates noise *** experiments on artificial and real-world partial label datasets show that our approach significantly outperforms state-of-the-art counterparts on classification prediction.

关键词： disambiguation partial label learning similarity and dissimilarity weak supervision

More studies are necessary to establish the effectiveness of Jinhuang powder in the treatment of diabetic foot

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World Journal of Diabetes 2022年第7期13卷 581-583页

作者： Ya-Wen Ye Zi-Yun Yan lian-ping He cui-ping li School of Medicine Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina

Diabetes mellitus is a common global public health problem that can cause serious illness and premature *** foot ulcer,one of the complications of diabetes,is a major cause of morbidity and mortality and is associated with many other devastating *** study found that a group of traditional Chinese medicine(TCM)can be used for treating diabetic foot *** and more attention is being paid to the use of Chinese medicine to heal diabetic *** the guidance of relevant theories of traditional Chinese medicine,more studies are needed to reveal the key active components and related signal pathways of TCM in the treatment of diabetic foot *** clinical study explored the treatment of diabetic foot with infection combined moist exposed burn ointment with Jinhuang ***,large-scale multi-center,double blind,randomized,placebo-controlled clinical trials and animal studies are necessary to establish the effectiveness of Jinhuang powder in the treatment of diabetic foot.

关键词： Diabetic foot Jinhuang powder Traditional Chinese medicine

Asperochones A and B,two antimicrobial aromatic polyketides from the endophytic fungus Aspergillus ***-2

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Chinese Chemical Letters 2024年第9期35卷 206-209页

作者： Hong Zhang cui-ping li li-li Wang Zhuo-Da Zhou Wen-Sen li ling-Yi Kong Ming-Hua Yang Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Two novel fungal metabolites,asperochones A and B,were obtained from an Aspergillus *** structures were determined by 1D/2D nuclear magnetic resonance(NMR)spectroscopy,high resolution electrospray ionization mass spectroscopy(HRESIMS),and single-crystal X-ray diffraction *** A possesses an intriguing skeleton bearing 5/6/6/6/7/5/5/5 octacyclic ring system,and asperochone B also exhibits an unusual carbon skeleton with five stereochiral *** structures were proposed as heterotrimeric and heterodimeric products of aromatic *** addition,asperochone A exhibited a potential anti-tuberculosis effect since it showed a moderate potency against Mycobacterium smegmatis.

关键词： Aspergillus sp. Asperochones A and B Aromatic polyketides Heterotrimeric compound Anti-tuberculosis effect Antifibrotic activity

Ring-opening Polymerization ofε-Caprolactone Using Lanthanide Tris(4-tert-butylphenolate)s as a Single-component Initiator

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Chinese Chemical Letters 2003年第10期14卷 1021-1023页

作者： cui ping YU, li Fang ZHANG, Zhi Quan SHEN Institute of Polymer Science, Zhejiang University, Hangzhou 310027 Institute of Polymer Science Zhejiang University Hangzhou 310027 China

The ring-opening polymerization of e-caprolactone (CL) initiated by novel single lanthanide tris(4-tert-butylphenolate)s [Ln(OTBP)3] is reported. Single-component La(OTBP)3 can effectively prepare polycaprolactone (PCL) with over 90% yield and viscosity average molecular weight about 60 x 10 under quite mild conditions: molar ratio of CL to initiator is 1000, 60 C, 2 h in toluene. Mechanism study indicates that the monomer inserts into the growing chain via the break of acyl-oxygen bond of CL.

关键词： Lanthanide tris(4-tert-butylphenolate)s e-caprolactone ring-opening polymerization.

Analysis of Solutions of the Holling-Tanner Model

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Acta Mathematicae Applicatae Sinica 2024年

作者： Ying-chao HAO Kun-lun HUANG Xin-tian JIA cui-ping li School of Mathematical Sciences Beihang University

In this paper we consider a kind of predator-prey model named Holling-Tanner model. Firstly, we prove all solutions of this model to be bounded from above. Secondly, we find a positive invariant set of the model, and prove the existence of stable limit cycle in this invariant set by Poincar′e-Bendixson theorem for the unstable equilibrium. Thirdly, we get the region of parameters in which the corresponding stable equilibrium are also globally asymptotically stable. Lastly, we give a bifurcation diagram and illustration with two limit cycles for special parameters through numerical simulation. By our knowledge, the invariant set constructed in this paper is better than that in the book written by Murray.

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Test evaluation for vertical fracture wells in low permeability reservoir

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Journal of Energy and Power Engineering 2009年第9期2卷 32-35页

作者： cui li-ping HE Shun-li MOE Key Laboratory for Petroleum Engineering China University of Petroleum Beo＇ing 102249 China

As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test analysis methods are of slow fitting speed and low fitting precision. In this paper, we first use a comprehensive evaluation method of analytical well testing, numerical well testing and well testing design. Many dynamic parameters such as fracture length, fracture conductivity, skin factor, etc are obtained. An example to illustrate accurate results of this method is given.

关键词： test evaluation fracture wells low permeability reservoir fracturing effect

Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong Hu Wenyi lian Kang Hu Qiuju li Xueliang cui Tengyu Yao Laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)