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Generalized Dirichlet Normal Ordering in Open Bosonic Strings

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Communications in Theoretical Physics 2009年第1期51卷 110-114页

作者： cao zhen-bin DUAN Yi-Shi Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

Generally, open string boundary conditions play a nontrivial role in string theory. For example, in the presence of an antisymmetric tensor background field, they will lead the spacetime coordinates noncommutative. In this paper, we mainly discuss how to build up a generalized Dirichlet normal ordered product of open bosonic string embedding operators that satisfies both the equations of motion and the generalized Dirichlet boundary conditions at the quantum level in the presence of an antisymmetric background field, as the generalized Neumann case has already been discussed in the literature. Further, we also give a brief check of the consistency of the theory under the newly introduced normal ordering.

关键词： boundary conditions normal ordering

Some Topological Properties of Anyons

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Communications in Theoretical Physics 2008年第11期50卷 1155-1158页

作者： cao zhen-bin LIU Yu-Xiao DUAN Yi-Shi Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper,starting with the well known U(1)Chern-Simons Lagrangian and the covariant derivative ofa complex scalar matter field,we give a detailed discussion of some topological properties of *** show that the'basic'charge carried by anyons has an inner structure and can be decomposed in terms of the Chern-Simons couplingand the gauge coupling constants of the *** some incorrect results obtained in the literature are revised.

关键词： anyon complex scalar held

Antitumor and anti-angiogenic activity of Ganoderma lucidum polysaccharides peptide

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Acta Pharmacologica Sinica 2004年第6期25卷 131-136页

作者： Qi-zhen cao, Zhi-bin LIN1 Department of Pharmacology, Health Science Center, Peking University, Beijing 100083, China Department of Pharmacology Health Science Center Peking University 100083

AIM: To investigate the antitumor and anti-angiogenic activity of Ganoderma lucidum polysaccharides peptide (GLPP). METHODS: Antitumor effect of GLPP was observed in tumor-bearing mice in vivo. At the same time, the effects of GLPP on proliferation of tumor cells and human umbilical cord vascular endothelial cell (HUVEC) were detected by MTTassay in vitro. Subsequently, spleen lymphocytes proliferation of nude mice was stimulated by LPS or ConA. To investigate the anti-angiogenic effect of GLPP, GLPP 80 μg per disc and GLPP-treated serum 10 μL per disc were added to the chick chorioallantoic membrane (CAM) respectively in vivo. RESULTS: GLPP 50, 100, and 200 mg/kg inhibited growth of Sarcoma 180 in BALB/c mice markedly by 35.2 %, 45.2 %, and 61.9 %, respectively. GLPP which was directly added to the cultured medium did not inhibit PG cell proliferation in vitro; but GLPP-treated serum 50, 100, 200 mg/kg potently inhibited PG cell proliferation by 22.5 %, 26.8 %, and 30.3 %, respectively; and reduced the xenograft (human lung carcinoma cell PG) in BALB/c nude mice greatly in vivo by 55.5 %, 46.0 %, and 46.8 %, respectively. Lymphocytes proliferation of nude mice could be stimulated by LPS 5 mg/Lbut not by ConA 2.5 mg/L, indicating that GLPP could not promote the T lymphocyte proliferation and neutral red phagocytosis of peritoneal macrophages of nude mice. The CAM assay showed that GLPP and GLPP-treated serum had anti-angiogenic effect. GLPP (1, 10, and 100 mg/L) inhibited HUVEC proliferation in vitro with the inhibitory rate of 9.4 %, 15.6 %, and 40.4 %, respectively. CONCLUSION: GLPP has antitumor and anti- angiogenic activity. The anti-angiogenesis of GLPP may be a new mechanism underlying its anti-tumor effects.

关键词： Ganoderma lucidum polysaccharides sarcoma 180 adenocarcinoma lung neoplasms lympho- cyte proliferation peritoneal macrophages angiogenesis nude mice

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傅里叶变换、拉普拉斯变换和伽博变换的关系

大学物理 2023年第7期42卷 21-23页

作者：曹贞斌中国石油大学(华东)理学院山东青岛266580

傅里叶变换、拉普拉斯变换和伽博变换,作为三种常见的积分变换,无论在数学物理的理论研究中还是在各种工程应用中,都有着极重要的价值.本文以傅里叶变换为中心,从逐级修正的角度,详细阐明了三者的理论渊源.

关键词：傅里叶变换拉普拉斯变换伽博变换

Aperiodically semi-intermittent-based fixed-time stabilization and synchronization of delayed discontinuous inertial neural networks

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Science China(Information Sciences) 2025年第1期68卷 238-254页

作者： Guodong ZHANG Jinde cao School of Mathematics and Statistics South-Central Minzu University School of Mathematics Southeast University

This article concentrates on the fixed-time stabilization(FS) and fixed-time synchronization(FTS) of discontinuous inertial neural networks(DINNs) with distributed delays. Using mathematical induction to a new differential equality, a novel fixed-time stability lemma is constructed. Then, by designing an aperiodically semi-intermittent switching control and combining it with the theory of nonsmooth analysis, some novel criteria on the FS and FTS of DINNs are obtained. Unlike the methods used in most existing studies, the FS and FTS results are structured using the newly proposed fixed-time stability lemma and the nonreduced-order approach, resulting in broader practical applications and strengthening the scientific quality of the derived results. Lastly, numerical simulations and applications proffer the effectiveness of the established FS and FTS criteria.

关键词： inertial neural networks fixed-time synchronization semi-intermittent switching control nonreduced-order approach fixed-time stabilization

3T磁共振增强全心冠状动脉成像技术临床应用价值

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中华心血管病杂志 2011年第4期39卷 329-333页

作者：曹桢斌孔祥泉常丹丹刘定西华中科技大学同济医学院附属协和医院放射科武汉430022

目的探讨自由呼吸导航门控3 T磁共振增强全心冠状动脉三维成像技术临床应用可行性及其价值.方法应用自由呼吸导航3 T磁共振增强全心冠状动脉三维成像方法对临床疑似冠心病患者行全心冠状动脉成像,增强采用钆贝葡胺注射液（0.2 mmol/kg... 详细信息

目的探讨自由呼吸导航门控3 T磁共振增强全心冠状动脉三维成像技术临床应用可行性及其价值.方法应用自由呼吸导航3 T磁共振增强全心冠状动脉三维成像方法对临床疑似冠心病患者行全心冠状动脉成像,增强采用钆贝葡胺注射液（0.2 mmol/kg）静脉缓慢注射,流率0.3ml/s.数据经后处理获得冠状动脉主要分支图像,评价图像质量,并以选择性冠状动脉造影检查结果为参照标准,采用9段划分法评价冠状动脉主要分支的有意义狭窄（＞50%）,判断磁共振增强冠状动脉成像对冠心病的诊断准确性及其价值.结果26例病例中23例顺利完成磁共振检查,平均扫描时间为（10.4±2.1）min.选择性冠状动脉造影显示的202个节段中,磁共振增强冠状动脉成像显示可评价节段178个（88.1%）,以近、中段图像质量较好.与选择性冠状动脉造影比较,磁共振增强冠状动脉成像在显示近段及中段可评价节段上差异无统计学意义（P＞0.05）.磁共振冠状动脉成像显示阳性9例,阴性14例.选择性冠状动脉造影显示11例阳性,12例阴性.磁共振冠状动脉成像有意义的狭窄总体诊断符合率91.3%（21/23）,灵敏度81.8%（9/11）,特异度88.5%（169/191）,阴性预测值98.8%（9/31）.结论自由呼吸导航门控3 T磁共振增强全心冠状动脉三维成像技术能够对冠状动脉近中段有意义的狭窄进行初步评估,一致性较好.但对冠状动脉远段及小分支狭窄的评估有一定限度.

关键词：冠状动脉疾病冠状血管造影术磁共振血管造影术

Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 164-170页

作者： WU Min cao Kailei XIAO Weirong YU Zetai cao Jierong DING Qingjun LI Jinhui China Railway Construction Corporation Harbour and Channel Engineering Bureau Group Co. LTDZhuhai 519000China Con-struction Headquarters of Zhoushan Liuheng Bridge Phase II Project Zhoushan 316000China China Railway Construction Bridge En-gineering Bureau Group Co. LTDTianjin 300000China State Key Laboratory of Silicate Material for Architecture(Wuhan University of Technology) Wuhan 430070China College of Materials Science and Engineering Wuhan Textile UniversityWuhan 430200China

The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 *** results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack *** addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate *** damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC ***,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution.

关键词： concrete external sulfate attack damage evolution situ X-ray computed tomography

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen CHEN Wei cao bingwei LIU Xinhui LI Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (CHP) gasification porous media combustion power generation

Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期34卷 223-241页

作者： WEI Xinyi ZHANG Nan ZHANG Zhaoli cao Xiaoling YUAN Yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

关键词： copper metal foam heat transfer enhancement phase change materials regionalized enhancement