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Chinese Chemical Letters 2016年第6期27卷 938-942页

作者： Hua Chen shun-Kai Xing fang Gao Na Li Xiao-Liu Li Ming Meng Key Laboratory of Chemical Biology of Hebei Province College of Chemistry and Environmental Science Hebei University Medical School Hebei University

Several novel C-pseudonucleosides containing thiazolidin-4-one and phenyl connected by acetamide bond were rationally designed and easily synthesized at room temperature by using the unprotected sugar aldehyde as the starting material. The effects of the compounds on Con A-induced T cell proliferation were evaluated at five concentrations of 5, 10, 25, 50, and 100 mmol/L Interestingly,compounds 7a and 8a（n = 2, R = H） exhibited immunostimulating activities, while compounds 5a, 6a（n = 1, R = H） and 7b, 8b（n = 2, R = CH3） showed immunosuppressive activities. Another two compounds 5 b and 6b（n = 1, R = CH3） had no immunomodulating activities. These initial biological results suggested that subtle structural changes to the phenyl and acetamide bond of C-pseudonucleosides could have a significant effect on T cell proliferation bias, although it was difficult to formulate a rigorous structureactivity relationship based on the observed activities.

关键词： Immunomodulator C-Pseudonucleosides Thiazolidin-4-one Acetamide bond SAR analysis

High strength bimetallic composite material fabricated by electroslag casting and characteristics of its composite interface

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China Foundry 2016年第6期13卷 389-395页

作者： Tian-shun Dong Jin-hai Liu Qian fang Guo-lu Li Jian-jun Zhang School of Material Science and Engineering Hebei University of Technology

Bimetallic composite material of bainitic steel and PD3 steel was produced with electroslag casting process, and element distribution of its composite interface was investigated by theoretical calculation and energy dispersive spectrometer(EDS). Results show that the tensile strength(1,450 MPa), hardness(HRC 41-47) and impact toughness(94.7J·cm^(-2)) of bainitic steel were comparatively high, while its elongation was slightly low(4.0%). Tensile strength(1,100 MPa), hardness(>HRC 31) and elongation(7.72%) of the interface were also relatively high, but its impact toughness was low at 20.4 J·cm^(-2). Results of theoretical calculation of the element distribution in the interface region were basically consistent with that of EDS. Therefore, electroslag casting is a practical process to produce bimetallic composite material of bainitic steel and PD3 steel, and theoretical calculation also is a feasible method to study element distribution of their interface.

关键词： electroslag casting bimetallic composite material bainitic steel interface

Dynamic recrystallization behavior of Fe–20Cr–30Ni–0.6Nb–2Al–Mo alloy

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Rare Metals 2019年第2期38卷 181-188页

作者： Rui Luo Qi Zheng Jing-Jing Zhu shun Guo Dong-Sheng Li Gui-fang Xu Xiao-Nong Cheng School of Materials Science and Engineering Jiangsu University

Single-pass compression tests of an aluminaforming austenite(AFA) alloy(Fe–20Cr–30Ni–0.6Nb–2Al–Mo) were performed using a Gleeble-3500 thermal–mechanical simulator. By combining techniques of electron back-scattered diffraction(EBSD) and transmission electron microscopy(TEM), the dynamic recrystallization(DRX) behavior of the alloy at temperatures of 950–1100 ℃ and strain rates of 0.01–1.00 s^(-1) was investigated. The regression method was adopted to determine the thermal deformation activation energy and apparent stress index and to construct a thermal deformation constitutive model. Results reveal that the flow stress is strongly dependent on temperature and strain rate and it increases with temperature decreasing and strain rate increasing. The DRX phenomenon occurs more easily at comparably higher deformation temperatures and lower strain rates. Based on the method for solving the inflection point via cubic polynomial fitting of strain hardening rate(h) versus strain(e) curves, the ratio of critical strain(ec) to peak strain(ep) during DRX was precisely predicted. The nucleation mechanisms of DRX during thermal deformation mainly include the strain-induced grain boundary(GB)migration, grain fragmentation, and subgrain coalescence.

关键词： Alumina-forming austenitic alloy Constitutivemodel Dynamic recrystallization Critical strain Straininduced grain boundary migration

Water Modeling of Twin-Roll Strip Casting

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Journal of Iron and Steel Research International 2006年第1期13卷 14-17页

作者： WANG Bo ZHANG Jie-yu FAN Jun-fei ZHAO shun-li fang Yuan AN Sheng-li School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Material and Metallurgical School Inner Mongolia University of Science and Technology Baotou 014010 Inner Mongolia China College of Materials Science and Engineering Shanghai University Shanghai 200072 China Research Institute Baoshan Iron and Steel Co Ltd Shanghai 201900 China

Twin-roll strip casting is regarded as a prospective technology of near net shape continuous casting. The fluid flow field and level fluctuation in the pool have a strong influence not only on composition and temperature homogeneity of pool, but also on the strip quality. A 1 ： 1 water model of a twin-roll strip caster was set up based on the criteria of Froude number and Reynold number similarity. The level fluctuation was measured. The influence of pool depth, casting speed and feeding system configuration on level fluctuation in the pool was studied. The experimental results provided a basis for the optimization of feeding system and process parameters.

关键词： twin-roll strip casting level fluctuation water modeling

Low-mass and high-mass supermassive black holes in radio-loud AGNs are spun-up in different evolution paths

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Research in Astronomy and Astrophysics 2019年第10期19卷 59-64页

作者： Jing Wang Min-Zhi Kong shun-fang Liu Da-Wei Xu Qiang Zhang Jian-Yan Wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology Guangxi University Nanning 530004 China Key Laboratory of Space Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing 100049 China Department of Physics Hebei Normal University Shijiazhuang 050024 China

How supermassive black holes(SMBHs) are spun-up is a key issue in modern astrophysics. As an extension to the study in Wang et al., here we address the issue by comparing the host galaxy properties of nearby(z 10^7.9 M⊙)have a preference for being spun-up in classical bulges, and low-mass SMBHs(i.e., MBH = 10^6-10^7 M⊙)in pseudo-bulges. This dichotomy suggests and confirms that high-mass and low-mass SMBHs are spun-up in different ways, i.e., a major "dry" merger and a secular evolution respectively.

关键词： galaxies bulges-galaxies nuclei-galaxies Seyfert

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Chinese Medical Sciences Journal 2011年第3期26卷 137-140页

作者： shun-hua Zhang fang-tian Dong Jin Mao Ai-ling Bian Department of Ophthalmology Peking Union Medical College HospitalChinese Academy of Medical Sciences ＆ Peking Union Medical CollegeBeijing 100730China

Objective To evaluate the predictive factors of refractory glaucoma treated with diode laser transscleral cyclophotocoagulation(TSCP) in a midterm *** Fifty-four consecutive patients(54 eyes) with refractory glaucoma were enrolled and underwent TSCP(power of 1.5-2.0 W,exposure time of 2 seconds and 20-50 applications).Patients were regularly followed up for 12 *** pressure(IOP) was measured before TSCP treatment and at each follow-up *** were divided into the sensitive and insensitive groups according to the effect of a single treatment of TSCP on *** success rate was defined as the percentage of eyes achieving an IOP between 5 and 21 mm Hg following TSCP therapy at their final follow up *** of age between the sensitive and insensitive groups was evaluated with Independent-samples T test and that of gender distribution of two groups was evaluated with Fisher's exact *** success rate of different types of glaucoma to TSCP was *** A total of 32 patients were sensitive to TSCP(sensitive group) and 22 patients were insensitive to TSCP(insensitive group).The success rates of female(77.8%,14/18) and cases being over 50 years(71.4%,20/28) were higher than those of male(50.0%,18/36) and ones being under 50 years(46.2%,12/26)(all P>0.05).The age of the sensitive and insensitive groups was 56.0±15.5 and 46.4±15.4 years,respectively(P=0.029).The age(P=0.029) and gender distribution(P=0.046) of the two groups had significant *** success rate of neovascular glaucoma,primary angle-closure glaucoma,primary open angle glaucoma,traumatic glaucoma,uveitic glaucoma,and secondary glaucoma after silicone oil injection to TSCP was 57.1%,100.0%,50.0%,20.0%,81.8%,and 0%,*** Age,gender,and type of glaucoma appear to be associated with effect of TSCP on IOP control.

关键词： predictive factor diode laser transscleral cyclophotocoagulation intraocular pressure

Antimony Potassium Tartrate Stabilizes Wide-Bandgap Perovskites for Inverted 4-T All-Perovskite Tandem Solar Cells with Efficiencies over 26%

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Nano-Micro Letters 2023年第7期15卷 204-217页

作者： Xuzhi Hu Jiashuai Li Chen Wang Hongsen Cui Yongjie Liu shun Zhou Hongling Guan Weijun Ke Chen Tao Guojia fang Key Laboratory of Artificial Micro/Nano Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072People’s Republic of China

Wide-bandgap(WBG)perovskites have been attracting much attention because of their immense potential as a front light-absorber for tandem solar ***,WBG perovskite solar cells(PSCs)generally exhibit undesired large open-circuit voltage(VOC)loss due to light-induced phase segregation and severe non-radiative recombination ***,antimony potassium tartrate(APTA)is added to perovskite precursor as a multifunctional additive that not only coordinates with unbonded lead but also inhibits the migration of halogen in perovskite,which results in suppressed non-radiative recombination,inhibited phase segregation and better band energy ***,a APTA auxiliary WBG PSC with a champion photoelectric conversion efficiency of 20.35%and less hysteresis is *** maintain 80%of their initial efficiencies under 100 mW cm^(-2)white light illumination in nitrogen after 1,000 ***,by combining a semi-transparent WBG perovskite front cell with a narrow-bandgap tin–lead PSC,a perovskite/perovskite four-terminal tandem solar cell with an efficiency over 26%is *** work provides a feasible approach for the fabrication of efficient tandem solar cells.

关键词： Perovskite solar cell Tandem Wide bandgap Multifunctional additive

Stability Study on the Bucket Foundation with Multi-Compartment During the Floating-up Process Considering Air Compressibility

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China Ocean Engineering 2023年第6期37卷 975-988页

作者： YE fang-di LIAN Ji-jian GUO Yao-hua WANG Hai-jun XIAO Tian-run XIONG Dong-zhi YU Tong-shun State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Tianjin University of Technology Tianjin 300384China College of Engineering Ocean University of ChinaQingdao 266100China

In the process of developing offshore wind power towards deeper waters,the advantages of the bucket foundation in terms of integrated construction and economy are becoming increasingly *** contrast to conventional floating bodies,the air-floating bucket foundations can achieve self-floating with the help of the air in the compartment and adjust its buoyancy and stability by controlling the air volume in the *** construction process of the bucket foundation involves the control of air in the compartment,thus making it more difficult to *** after the prefabrication of the bucket foundation,the stability of the bucket foundation at the floating-up stage is particularly *** stability of a multi-compartment bucket foundation during the floating-up process cannot be accurately evaluated as the existing theoretical method of air-floating structures does not adequately consider air *** ensure the safety of the floating-up process,a theoretical method based on the idea of intact stability has been developed to analyze the stability of the air-floating bucket foundations,which will allow accurate calculation of the righting arm for different tilt states and critical air leakage *** the same time,accuracy and feasibility of the proposed theoretical method are verified through indoor model tests and practical operation of the prototype structure during the floating-up *** addition,measures to enhance the stability of the bucket foundation are proposed through sensitivity analysis of influencing factors.

关键词： offshore wind power bucket foundation air-floating structure stability

Selection and application of wavelet transform in high-frequency sequence stratigraphy analysis of coarse-grained sediment in rift basin

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Petroleum Science 2024年第5期21卷 3016-3028页

作者： Ling Li Zhi-Zhang Wang shun-De Yin Wei-fang Wang Zhi-Chao Yu Wen-Tian Fan Zhi-Heng Zhang National Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Civil and Environmental Engineering Department University of WaterlooWaterlooONN2L5Z5Canada SINOPEC Petroleum Exploration and Production Research Institute Beijing101599China

Wavelet transformation is a widely used method in high-frequency sequence stratigraphic ***, the application is problematic since different wavelets always return the same sequence analysis results. To address this issue, we applied five commonly used wavelets to theoretical sequence models to document some application criteria. Five gradual scale-change sequence models were simplified from the glutenite succession deposition by gravity flows to form the fining-upwards cycle sequences(FUCS) and coarsening-upwards cycle sequences(CUCS). After conducting theoretical sequence model tests, the optimal wavelet(sym4) was selected and successfully used with actual data to identify the sequence boundaries. We also proposed a new method to optimize the scale of continuous wavelet transformation(CWT) for sequence boundary determination. We found that the balloon-like marks in scalograms of db4, sym4, and coif4 wavelet determine, respectively, the fourth-order sequence boundary, the thick succession sequence boundaries in FUCS, and the thick succession sequence in FUCS and CUCS. Comparing the sequence identification results shows that the asymmetric wavelets had an advantage in high-frequency sequence boundary determination and sedimentary cycle discrimination through the amplitude trend of the coefficient, in which the sym4 wavelet is the most effective. In conclusion, the asymmetry of wavelets is the first selection principle, of which asymmetric wavelets are more sensitive to sediment deposition by flood flows. The match of the wavelet between the sequence is the second selection principle, in which the correlation of time-frequency impacts the accuracy of sequence surface localization. However, the waveform of the wavelet is a visual and abstract parameter for sequence boundary detection. The appropriate wavelet for lacustrine sequence analysis is the asymmetric wavelet with a weak number of side lobes. The depositional flows, depositional process,and autogeni

关键词： Wavelet analysis High-resolution sequence Sedimentary cyclicity Asymmetric wavelets

Deciphering dynamic surface of PtRu alloy nanocatalysts to revisit their synergistic effects during the electrooxidation

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Science China Chemistry 2024年第7期67卷 2224-2233页

作者： Xiao-Chong Li Bo Wang Zhou Yu Qiang Wan Ju-fang Zheng Emmanuel Maisonhaute Xiao-shun Zhou Ya-Hao Wang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China Laboratoire Interface et Systèmes Electrochimiques CNRS UMR 8235Sorbonne UniversitéF-75252 Paris cedex 5France

Correlating dynamic structural transformation of catalysts with the surface intermediate species under operating conditions is critical for updating the understanding of structure–performance ***,we probe the electrochemical potentialdependent surface structures and adsorbed intermediates on PtRu binary alloy nanocatalysts to revisit its synergistic mechanisms for CO electrooxidation enhanced ***-situ spectral characteristics by using modified shell-isolated nanoparticle-enhanced Raman spectroscopy,show that in acidic solution,when the potential is positively scanned from 0.1 V to 1.5 V relative to reversible hydrogen electrode(RHE),the surface of the alloy catalyst evolves from metallic PtRu to adsorbed oxygen gradually covering and accumulating on Ru sites(denoted as PtRuO_(x),x≤2),forming segregated RuO_(2),and finally forming a threedimensional oxide layer(denoted as 3D PtRuO_(4)).Moreover,molecular evidence associated with periodic density functional theory calculations reveals that electronic effects promote ruthenium to become more oxidizable and *** particular,we found here that ^(*)O and ^(*)OH at surface RuO_(x) sites are highly efficient CO oxidation active species in comparison to the same entities adsorbed on metallic Ru *** work sheds light on the complex surface dynamic process of practical Pt-based binary nanocatalysts and improves the understanding of synergistic mechanism for the development of fuel cell devices.

关键词： in-situ Raman spectroscopy surface evolution bifunctional mechanism PtRu electrooxidation

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