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Chemical Research in Chinese Universities 2006年第1期22卷 40-44页

作者： li Qian-rong XUE song YIN Hao Hefei National Laboratory for Physical Sciences at Microscale and Department of Chemistry University of Science and Technology of China Hefei 230026 P. R. China

The electron impact （EI） time-of-flight mass spectra （TOFMS） of the title compounds （ thioxo-Biginelli compounds） were studied to establish their fragmentation pathways. With a TOF instrument of high resolution, the exact mass for each fragment was determined. These data were used to infer the molecular formulas and the ionic elemental compositions for all the compounds through interpretation by software. By further applying chemical intuition, majority of the fragmentation ions were fully assigned. All the compounds give strong signals（ average 76% ） for their molecular ions in the El spectra. Two kinds of characteristic fragmentation pathways from the molecular ion were observed. One is related to the loss of the ester group, forming a resonance stabilized ion with a moderate abundance（ average 40% ）. The other concerns the loss of the aromatic-ring radical, forming another resonance stabilized ion at m/z 199 with a high abundance（ average 79% ）, from which further important fragmentations including the formation of an ion at m/z 171 （average 24% ） by the loss of C2H2 （via the McLafferty rearrangement）, and an ion at m/z 153（ average 10% ） by the elimination of a water molecule preceed. In addition, ion [ M - Et ]^＋ with a high abundance（average 62% ） is a characteristic for the Biginelli compounds with an ethoxycarbonyl group. Differences and similarities among the fragmentations observed from the EI-TOFMS of oxo-Biginelli compounds are discussed.

关键词： Beginelli compound 3,4-Dihydropyrimidinthione Time-of-flight mass spectrometry Electron impact

Preparation and application of efficient TiO_2 /ACFs photocatalyst

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Journal of Environmental Sciences 2006年第5期18卷 979-982页

作者： liU Jian-hua YANG rong li song-mei School of Materials Science and Engineering Beihang University Beijing 100083 China

Activated carbon fibers （ACFs） supported titanium dioxide （TiO2） photocatalyst was developed by sol-gel method. The surface morphology and microstructure of the photocatalyst were characterized with scan electron microscope（SEM）, X-ray diffraction patterns and specific surface area analysis. The prepared photocatalyst is specially helpful for the removal of low molecular weight organic pollutants in wastewater. Decomposition efficiency of methylene blue solution by TiO2/ACFs catalyst reached almost 100% under 60 min reaction, while the decomposition efficiency by pure TiO2 was only 25% under 3 h reaction. The mineralization of toluene aqueous solution was measured by total organic carbon instrument, and the evolution of intermediate species was detected by gas chromatograph instrument. The results indicated that the prepared photocatalyst not only enhanced the photoactivity of TiO2, but also suppressed the emergence of intermediate species, which may be more deleterious to human. The enhancement of photocatalysis was due to increased efficiency of adsorption and desorption, which were control steps in heterogeneous photocatalysis.

关键词： titanium dioxide activated carbon fibers photocatalysis toluene methylene blue

Genetic Diversity： Geographical Distribution and Toxin Profiles of Microcystis Strains （Cyanobacteria） in China

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Journal of Integrative Plant Biology 2007年第3期49卷 262-269页

作者： Zhong-Xing Wu Nan-Qin Gan li-rong song State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Twenty strains of Microcystis Kütz were isolated from different freshwater bodies in China to analyze the diversity, geographical distribution and toxin profiles. Based on whole-cell polymerase chain reaction of cpcBA-IGS nucleotlde sequence, the derived neighbor-joining （NJ） and maximum parsimony （MP） trees Indicate that these strains of Microcystis can be divided into four clusters. The strains from south, middle and north region of China formed distinct lineages, suggesting high diversity and a geographical distribution from south to north locations. Moreover, the results being indicating high variable genotypes of the strains of the Microcystis strains from the same lake show that there Is high diversity of Microcystis within a water bloom population. Comparing the results of the present study with those reported for compared with 43 strains of Microcystis from other locations, also reveals Chinese strains have high similarity with those from regions in the North Hemispherical. This suggests that the Microcystis strains In the world might have a geographical distribution. Analysis of 30 strains using the primers MCF/TER and TOX2P/TOX2M showed that there was no correlation between the gene of cpcBA-IGS and the presence of racy. Toxic strains were founded to be predominant in different water bodies throughout China.

关键词： diversity geographical distribution microcystin Microcystis

Prediction of different stages of rectal cancer: Texture analysis based on diffusion-weighted images and apparent diffusion coefficient maps

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World Journal of Gastroenterology 2020年第17期26卷 2082-2096页

作者： Jian-Dong Yin li-rong song He-Cheng Lu Xu Zheng Department of Radiology Shengjing Hospital of China Medical UniversityShenyang 110003Liaoning ProvinceChina College of Medicine and Biological Information Engineering Northeastern UniversityShenyang 110036Liaoning ProvinceChina Department of Clinical Oncology Shengjing Hospital of China Medical UniversityShenyang 110011Liaoning ProvinceChina

BACKGROUND It is evident that an accurate evaluation of T and N stage rectal cancer is essential for treatment *** has not been extensively investigated whether texture features derived from diffusion-weighted imaging(DWI)images and apparent diffusion coefficient(ADC)maps are associated with the extent of local invasion(pathological stage T1-2 vs T3-4)and nodal involvement(pathological stage N0 vs N1-2)in rectal *** To predict different stages of rectal cancer using texture analysis based on DWI images and ADC *** One hundred and fifteen patients with pathologically proven rectal cancer,who underwent preoperative magnetic resonance imaging,including DWI,were enrolled,*** ADC measurements(ADCmean,ADCmin,ADCmax)as well as texture features,including the gray level co-occurrence matrix parameters,the gray level run-length matrix parameters and wavelet parameters were calculated based on DWI(b=0 and b=1000)images and the ADC *** sample t-tests or Mann-Whitney U tests were used for statistical *** logistic regression analysis was conducted to establish the *** predictive performance was validated by receiver operating characteristic curve *** Dissimilarity,sum average,information correlation and run-length nonuniformity from DWIb=0 images,gray level nonuniformity,run percentage and run-length nonuniformity from DWIb=1000 images,and dissimilarity and run percentage from ADC maps were found to be independent predictors of local invasion(stage T3-4).The area under the operating characteristic curve of the model reached 0.793 with a sensitivity of 78.57%and a specificity of 74.19%.Sum average,gray level nonuniformity and the horizontal components of symlet transform(SymletH)from DWIb=0 images,sum average,information correlation,long run low gray level emphasis and SymletH from DWIb=1000 images,and ADCmax,ADCmean and information correlation from ADC maps were identified as independent pr

关键词： Rectal cancer Diffusion weighted imaging Apparent diffusion coefficient Texture analysis

Effects of Salt Stress on Carbohydrate Metabolism in Desert Soil Alga Microcoleus vaginatus Gom

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Journal of Integrative Plant Biology 2006年第8期48卷 914-919页

作者： Lan-Zhou Chen Dun-Hai li li-rong song Chun-Xiang Hu Gao-Hong Wang Yong-Ding liu State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 China School of Resource and Environmental Sciences Wuhan University Wuhan 430072 China

The effects of salt stress on carbohydrate metabolism in Microcoleus vaginatus Gom., a cyanobacterium isolated from desert algal crusts, were investigated in the present study. Extracellular total carbohydrates and exopolysaccharides （EPS） in the culture medium produced by M. vaginatus increased significantly during the growth phase and reached a maximum during the stationary phase. The production of extracellular carbohydrates also significantly increased under higher salt concentrations, which was attributed to an increase in low molecular weight carbohydrates. In the presence of NaCI, the production of cellular total carbohydrates decreased and photosynthetic activity was impaired, whereas cellular reducing sugars, water-soluble sugars and sucrose content and sucrose phosphate synthase activity increased, reaching a maximum in the presence of 200 mmol/L NaCI. These parameters were restored to original levels when the algae were transferred to a non-saline medium. Sodium and K＋ concentrations of stressed cells decreased significantly and H＋-ATPase activity increased after the addition of exogenous sucrose or EPS. The results suggest that EPS and sucrose are synthesized to maintain the cellular osmOtic equilibrium between the intra-and extracellular environment, thus protecting algal cells from osmotic damage, which was attributed to the selective exclusion of cellular Na＋ and K＋ by H＋-ATPase.

关键词： carbohydrate metabolism desert cyanobacteria exopolysaccharides (EPS) osmotic equilibrium salt stress.

Node ranking based on graph curvature and PageRank

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CHINESE PHYSICS B 2025年第2期34卷 496-507页

作者： Qu, Hongbo song, Yu-rong li, Ruqi li, Min Jiang, Guo-Ping Nanjing Univ Posts & Telecommun Sch Comp Sci Nanjing 210023 Peoples R China Nanjing Univ Posts & Telecommun Coll Automat Nanjing 210023 Peoples R China Nanjing Univ Posts & Telecommun Coll Artificial Intelligence Nanjing 210023 Peoples R China

Identifying key nodes in complex networks is crucial for understanding and controlling their dynamics. Traditional centrality measures often fall short in capturing the multifaceted roles of nodes within these networks. The PageRank algorithm, widely recognized for ranking web pages, offers a more nuanced approach by considering the importance of connected nodes. However, existing methods generally overlook the geometric properties of networks, which can provide additional insights into their structure and functionality. In this paper, we propose a novel method named Curv-PageRank (C-PR), which integrates network curvature and PageRank to identify influential nodes in complex networks. By leveraging the geometric insights provided by curvature alongside structural properties, C-PR offers a more comprehensive measure of a node's influence. Our approach is particularly effective in networks with community structures, where it excels at pinpointing bridge nodes critical for maintaining connectivity and facilitating information flow. We validate the effectiveness of C-PR through extensive experiments. The results demonstrate that C-PR outperforms traditional centrality-based and PageRank methods in identifying critical nodes. Our findings offer fresh insights into the structural importance of nodes across diverse network configurations, highlighting the potential of incorporating geometric properties into network analysis.

关键词： important nodes graph curvature complex networks network geometry 89.75.-k 89.75.Fb 02.40.-k

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尾缘修形的二元喷管内外流场数值研究

航空动力学报 2005年第3期20卷 389-393页

作者：李荣松王强额日其太北京航空航天大学能源与动力工程学院北京100083

针对美国第四代战斗机F-22在二元收-扩喷管设计应用上的特点,利用时间推进的有限体积法对二元喷管尾缘修形前后非矢量状态下的内外流混合流场进行了数值模拟。结果表明:二元喷管出口尾缘修形使得喷管出口下游流场中出现了很强的流向涡,... 详细信息

针对美国第四代战斗机F-22在二元收-扩喷管设计应用上的特点,利用时间推进的有限体积法对二元喷管尾缘修形前后非矢量状态下的内外流混合流场进行了数值模拟。结果表明:二元喷管出口尾缘修形使得喷管出口下游流场中出现了很强的流向涡,能够促进内外流的强化混合,对缩短高温核心区、加快尾喷流沿流向的温度衰减有明显效果,对抑制尾喷流的红外辐射有一定好处。

关键词：航空、航天推进系统二元收-扩喷管尾缘修形流向涡强化混合数值模拟

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 67-74页

作者： song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China School of Physical Science and Technology Ningbo UniversityNingbo 315211China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences(UCAS)Hangzhou 310024China Theoretical Physics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am Muhlenberg 1Golm 14476Germany

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition,yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT)left *** specific baryon chemical poten-tial,the first-order QCD phase transition agrees with the observational constraint of baryon ***,therefore,provides a scenario for phase transition gravitational waves(GWs)within the standard model of particle *** these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA)observations,the duration of this FoPT can be well constrained,and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

“逍遥”与“成仙”——《庄子》、《抱朴子内篇》生死观比较

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安徽大学学报（哲学社会科学版） 2008年第4期32卷 29-33页

作者：李松荣中山大学中文系广东广州510275

《庄子》和《抱朴子内篇》分别是道家学说和早期道教思想的经典,它们在对待生死的问题上存在较大差异:《庄子》从"道"的立场来观照死亡,在精神层面上解决了对死亡的超越问题;而《抱朴子内篇》则把"道"与神仙道教联系起来,认为成仙才是得... 详细信息

《庄子》和《抱朴子内篇》分别是道家学说和早期道教思想的经典,它们在对待生死的问题上存在较大差异:《庄子》从"道"的立场来观照死亡,在精神层面上解决了对死亡的超越问题;而《抱朴子内篇》则把"道"与神仙道教联系起来,认为成仙才是得"道"的标志。二者生死观的差异导致了葛洪对庄子思想的非议和指责。

关键词：《庄子》道家《抱朴子内篇》道教庄子葛洪生死观

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 45-53页

作者： lingxiao li Jing li Yanqi song Sujuan Qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China

In scenarios where a large amount of data needs to be learned,incremental learning can make full use of old knowledge,signif-icantly reduce the computational cost of the overall learning process,and maintain high *** this paper,taking the MaxCut problem as our example,we introduce the idea of incremental learning into quantum computing,and propose a Quantum Proactive Incremental Learning algorithm(QPIL).Instead of a one-off training of quantum circuit,QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices,proactively reducing large-scale problems to smaller ones to solve in steps,providing an efficient solution for ***,some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at ***,in each incremental phase,the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current *** perform experiments on 120 different small-scale graphs,and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR),time cost,anti-forgetting,and solv-ing *** particular,QPIL’s AR surpasses 20%of mainstream quantum baselines,and the time cost is less than 1/5 of *** idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale MaxCut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing