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Semi-gas kinetics model for performance modeling of flowing chemical oxygen-iodine lasers(COIL)

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Science China(Physics,Mechanics & Astronomy) 2004年第3期47卷 338-351页

作者： gao Zhi hu Limin SHEN Yiqing Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

A semi-gas kinetics (SGK) model for performance analyses of flowing chemical oxygen-iodine laser (COIL) is presented. In this model, the oxygen-iodine reaction gas flow is treated as a continuous medium, and the effect of thermal motions of particles of different laser energy levels on the performances of the COIL is included and the velocity distribution function equations are solved by using the double-parameter perturbational method. For a premixed flow, effects of different chemical reaction systems, different gain saturation models and temperature, pressure, yield of excited oxygen, iodine concentration and frequency-shift on the performances of the COIL are computed, and the calculated output power agrees well with the experimental data. The results indicate that the power extraction of the SGK model considering 21 reactions is close to those when only the reversible pumping reaction is considered, while different gain saturation models and adjustable parameters greatly affect the output power, the optimal threshold gain range, and the length of power extraction.

关键词： chemical oxygen-iodine laser (COIL), semi-gas kinetics (SGK) model, rate equation (RE) model, homogeneous broadening, inhomogeneous broadening, performance analysis, spectral line broadening (SLB) model.

Dynamic dam-reservoir interaction analysis including effect of reservoir boundary absorption

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Science China(Technological Sciences) 2007年第Z1期50卷 1-10页

作者： LIN gao DU JianGuo hu ZhiQiang School of Civil and Hydraulic Engineering Dalian University of TechnologyDalian 116024China School of Civil and Hydraulic EngineeringDalian University of TechnologyDalian 116024China School of Civil and Hydraulic EngineeringDalian University of TechnologyDalian 116024China

Based on the scaled boundary finite-element method, the governing equations for the analysis of dam-reservoir interaction including the reservoir boundary absorption are developed. Coupling with the equation of dam-unbounded foundation interaction, it can effectively carry out the earthquake response analysis of dameservoir-foundation system. The proposed approach has the advantages that the effect of compressibility of reservoir water as well as the energy absorption of reservoir boundary on the earthquake response of arch dams and gravity dams can be efficiently evaluated and higher accuracy can be achieved. In comparison with the methods available in the literature, the computational cost can be reduced to a great extent. It facilitates the application of earthquake response analysis of dam-reservoir-foundation system including reservoir boundary absorption to the engineering practice.

关键词： scaled boundary finite-element method dam-reservoir interaction reservoir boundary absorption

Heterogeneous Fracture Simulation of Three-point Bending Plain-concrete Beam with Double Notches

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Acta Mechanica Solida Sinica 2016年第3期29卷 232-244页

作者： Chuanchuan Zhang Xinhua Yang hu gao Hongping Zhu School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment 1037 Luoyu Road Wuhan 430074 China

Plain concrete is regarded as a two-phase material comprising randomly distributed aggregates and mortar matrix. A series of three-point bending concrete beams with symmetric or asymmetric double notches are modeled using the modified random aggregate generation and packing algorithm. The cohesive zone model is used as the fracture criterion and the cohesive el- ements are inserted into both the mortar matrix and the aggregate-mortar interfaces as potential micro-cracking zones. The dead and alive crack phenomena are studied experimentally and nu- merically; and the influences of notch location, aggregate distribution and gradation on fracture are numerically evaluated. Some important conclusions are given.

关键词： concrete beam double notches three-point bending fracture cohesive zone model

Ground state singlet-to-triplet conversion of copper corrole radical byβ-benzo-fusion

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Chinese Chemical Letters 2023年第8期34卷 412-415页

作者： Fan Wu hu gao Yue Zhao Zhen Shen State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Materials with facilely tunable spin configurations based on metal-radical coordination systems have potential applications for electronics and ***,we report the ground state conversion of copper corrole radicals from singlet to triplet via the extension of theπ-conjugation system by benzo-fusion at theβ-position of corrole *** spectroscopy,SQUID measurements and computational studies all support the ferromagnetic coupling between the Cu(II)center and corroleπ-radical of benzo-fused copper corrole 2-Cu,which is in sharp contrast with the antiferromagnetic coupling in regular non-extended copper *** triplet 2-Cu is highly stable in air,and X-ray diffraction analysis revealed its unique highly planar corrole *** work offers a promising strategy for creating high-spin systems in non-innocent metallocorroles.

关键词： Radicals Porphyrinoids Copper Ferromagnetic interaction Ring-fused systems

Enriching short text representation in microblog for clustering

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Frontiers of Computer Science 2012年第1期6卷 88-101页

作者： Jiliang TANG Xufei WANG huiji gao Xia hu huan LIU Computer Science ＆ Engineering Arizona State University Tempe AZ 85281 USA

Social media websites allow users to exchange short texts such as tweets via microblogs and user status in friendship networks. Their limited length, pervasive abbrevi- ations, and coined acronyms and words exacerbate the prob- lems of synonymy and polysemy, and bring about new chal- lenges to data mining applications such as text clustering and classification. To address these issues, we dissect some poten- tial causes and devise an efficient approach that enriches data representation by employing machine translation to increase the number of features from different languages. Then we propose a novel framework which performs multi-language knowledge integration and feature reduction simultaneously through matrix factorization techniques. The proposed ap- proach is evaluated extensively in terms of effectiveness on two social media datasets from Facebook and Twitter. With its significant performance improvement, we further investi- gate potential factors that contribute to the improved perfor- mance.

关键词： short texts text representation multi-languageknowledge matrix factorization social media

Boosting near-infrared photothermal/photoacoustic conversion performance of anthracene-fused porphyrin via paramagnetic ion coordination strategy

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Science China Chemistry 2023年第1期66卷 164-173页

作者： Fan Wu Yufen Sun hu gao Xu Zhi Yue Zhao Zhen Shen State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructureSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Designing stable molecules with efficient near-infrared(NIR) photothermal/photoacoustic performances is important for biological and environmental *** this article,we inserted paramagnetic Cu(Ⅱ) into tetraanthraporphyrin to generate a highly photostable molecule,Cu ANP,which demonstrated a sharp,intense Q band in the NIR region above 800 *** its diamagnetic Zn(Ⅱ)-coordinated analog Zn ANP that degraded rapidly under ambient light,Cu ANP has a low-lying singly unoccupied d orbital that quenched radioactive emission and reactive oxygen generation effectively,resulting in fast photothermal response,excellent photothermal conversion capacity and heat endurance under long-term laser irradiation in an organic solvent,in water after encapsulation as a nanocomposite,and in the solid *** ANP also exhibited an intense NIR photoacoustic response and was reversibly redox-active,displaying a broad band spreading to the NIR-Ⅱ window(700–1,300 nm) in the dicationic *** paramagnetic metal incorporation strategy can enhance the performance of photolabile NIR absorbing molecules for a variety of photothermal/photoacoustic applications.

关键词： porphyrinoids photothermal photoacoustic near-infrared paramagnetic

ent-Pimarane Diterpenoid Dimers from Sigesbeckia glabrescens with Potent Anti-inflammatory Activities

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Chinese Journal of Chemistry 2021年第12期39卷 3315-3321页

作者： Xiao-Xu gao Ying-Ying Zheng Xiao-Yu Zhang gao-Sheng hu Jing-Ming Jia An-hua Wang School of Traditional Chinese Materia Medica Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China

Chromatographic purification of Sigesbeckia glabrescens extracts led to three undescribed ent-pimarane diterpenoid dimers,named glabreside A—C(1-3).Their structures were confirmed by comprehensive spectroscopic analyses,and the structures of compound 1 and 3 were confirmed by X-ray *** results of anti-inflammatory activity assay showed that glabreside C(3)exhibited the most potent inhibition activity on nitric oxide(NO)production induced by lipopolysaccharide(LPS)in BV2 microglia compared with the other two *** C also increased the protein expression level of heme oxygenase-1(HO-1),and suppressed inducible nitric oxide synthase(iNOS)and cyclooxygenase 2(COX2)in LPS-stimulated BV2 ***,glabreside C exerts its anti-inflammatory effect by inhibiting AKT/MAPKs signaling *** findings indicate the vital role of ent-pimarane diterpenoid dimers in explaining the anti-inflammatory activity of *** and provide important evidence for further development and utilization of Sigesbeckiae *** results also suggest that glabreside C is a potential lead compound for anti-inflammatory drugs.

关键词： Siegesbeckia glabrescens Makino Terpenoids Biosynthesis Inflammatory Biological activity

Effects of feeding tyrosine and phenylalanine on the accumulation of phenylethanoid glycosides to Cistanche deserticola cell suspension culture

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Chinese Journal of Natural Medicines 2014年第5期12卷 367-372页

作者： hu gao-Sheng JIA Jing-Ming Doh Hoon Kim School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Joint Laboratory of Shenyang Pharmaceutical University Dong-A University College of Life Science and Natural Resources Dong-A University

AIM: To investigate the effects of feeding phenylalanine(Phe) and tyrosine(Tyr) on the accumulation of total phenolic compounds and four phenylethanoid glycosides(PeGs) to a cell suspension culture of the parasitic plant Cistanche deserticola. METHOD: A cell suspension culture of C. deserticola was established and precursors of different concentrations were fed. In each group, the cell was sampled at the 24th day after inoculation. The content of total phenolic compounds and four PeGs compounds were determined using the Folin-Ciocalteu method and an HPLC method, respectively. RESULTS: In the Phe fed cells, the maximum PeGs yield was achieved when Phe was fed at 1.5 mmol·L-1 and the yield reached 1.13 times the control cell concentration. In the Tyr fed cells, the maximum yield of PeGs was 1.60 times of control when 0.75 mmol·L-1 Tyr was fed to the cells. Furthermore, it was found that the salidroside yield was 4.01 times of control group when 5 mmol·L-1 Tyr was fed. CONCLUSION: Tyr is a better precursor for PeGs accumulation compared with Phe, and the rate limiting enzymes might be involved in the Tyr branch.

关键词： Cistanche deserticola Cell suspension culture Phenylalanine Tyrosine Precursor feeding RP-HPLC Salidroside Biosynthesis Phenylethanoid glycosides

Fast pre-stack multi-channel inversion constrained by seismic reflection features

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Petroleum Science 2023年第4期20卷 2060-2074页

作者： Ya-Ming Yang Xing-Yao Yin Kun Li Feng Zhang Jian-hu gao School of Geosciences China University of Petroleum(East China)QingdaoShandong266580China Pilot National Laboratory for Marine Science and Technology(Qingdao) QingdaoShandong266580China Shandong Provincial Key Laboratory of Deep Oil and Gas QingdaoShandong266580China China University of Petroleum-Beijing Beijing102249China Research Institute of Petroleum Exploration and Development-Northwest LanzhouGansu730020China

Classical multi-channel technology can significantly reduce the pre-stack seismic inversion uncertainty, especially for complex geology such as high dipping structures. However, due to the consideration of complex structure or reflection features, the existing multi-channel inversion methods have to adopt the highly time-consuming strategy of arranging seismic data trace-by-trace, limiting its wide application in pre-stack inversion. A fast pre-stack multi-channel inversion constrained by seismic reflection features has been proposed to address this issue. The key to our method is to re-characterize the reflection features to directly constrain the pre-stack inversion through a Hadamard product operator without rearranging the seismic data. The seismic reflection features can reflect the distribution of the stratum reflection interface, and we obtained them from the post-stack profile by searching the shortest local Euclidean distance between adjacent seismic traces. Instead of directly constructing a large-size reflection features constraint operator advocated by the conventional methods, through decomposing the reflection features along the vertical and horizontal direction at a particular sampling point, we have constructed a computationally well-behaved constraint operator represented by the vertical and horizontal partial derivatives. Based on the Alternating Direction Method of Multipliers (ADMM) optimization, we have derived a fast algorithm for solving the objective function, including Hadamard product operators. Compared with the conventional reflection features constrained inversion, the proposed method is more efficient and accurate, proved on the Overthrust model and a field data set.

关键词： Pre-stack multi-channel inversion Reflection features Fast optimization