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Chiral quantum heating and cooling with an optically controlled ion

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Light(Science & Applications) 2024年第7期13卷 1393-1400页

作者： jin-Tao Bu Jian-Qi Zhang Ge-Yi Ding Jia-Chong Li Jia-Wei Zhang Bin Wang Wen-Qiang Ding Wen-Fei Yuan {1. Chen Qi Zhong Ali keçebaş Şahin KÖzdemir Fei Zhou Hui jing Mang Feng State key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of Sciences430071 WuhanChina. university of the Chinese Academy of Sciences 100049 BeijingChina. Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology511458 GuangzhouChina. department of Engineering Science and Mechanics and Materials Research InstitutePennsylvania State UniversityUniversity ParkState CollegePA 16802USA. key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University410081 ChangshaChina. department of Physics Zhejiang Normal University321004 JinhuaChina

Quantum heat engines and refrigerators are open quantum systems,whose dynamics can be well understood using a non-Hermitian formalism.A prominent feature of non-Hermiticity is the existence of exceptional points(EPs),which has no counterpart in closed quantum *** has been shown in classical systems that dynamical encirclement in the vicinity of an EP,whether the loop includes the EP or not,could lead to chiral mode ***,we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs(LEPs),which include the effects of quantum jumps and associated noise—an important quantum feature not present in previous *** demonstrate,using a Paul-trapped ultracold ion,the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an *** witness the cycling direction to be associated with the chirality and heat release(absorption)of the quantum heat engine(quantum refrigerator).Our experiments have revealed that not only the adiabaticity breakdown but also the Landau–Zener–Stückelberg process play an essential role during dynamic encircling,resulting in chiral thermodynamic *** observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

关键词： quantum chiral dynamical

Solving the Euclidean Steiner Minimum Tree Using Cellular Stochastic Diffusion Search Algorithm

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Journal of Shanghai Jiaotong university(Science) 2011年第6期16卷 734-741页

作者：张瑾赵雅靓马良 Institute of Image Processing and Pattern Recognition Henan University School of Management University of Shanghai for Science and Technology

The Euclidean Steiner minimum tree problem is a classical NP-hard combinatorial optimization *** of the intrinsic characteristic of the hard computability,this problem cannot be solved accurately by efficient algorithms up to *** to the extensive applications in real world,it is quite important to find some heuristics for *** stochastic diffusion search algorithm is a newly population-based algorithm whose operating mechanism is quite different from ordinary intelligent algorithms,so this algorithm has its own advantage in solving some optimization *** paper has carefully studied the stochastic diffusion search algorithm and designed a cellular automata stochastic diffusion search algorithm for the Euclidean Steiner minimum tree problem which has low time *** results show that the proposed algorithm can find approving results in short time even for the large scale size,while exact algorithms need to cost several hours.

关键词： Euclidean Steiner minimum tree stochastic diffusion search cellular automata

Semantic Search among Heterogeneous Biological Databases Based on Gene Ontology

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 365-370页

作者： Shun-liang CAO, Lei QIN1. Wei-Zhong HE1. Yang ZHONG2, Yang-Yong ZHU, and Yi-Xue LI1.3* {1. of Computing and Information Technology, Fudan university, Shanghai 200433, china Shanghai Center for Bioinformation 1. Technology, Shanghai 200235, china School of Life Sciences, Fudan university, Shanghai 200433, china Bioinformation Center of Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031. china department of Computing and Information Technology Fudan University Shanghai China

Semantic search is a key issue in integration of heterogeneous biological databases. In this paper, we present a methodology for implementing semantic search in BioDW, an integrated biological data warehouse. Two tables are presented: the DB2GO table to correlate Gene Ontology (GO) annotated entries from BioDW data sources with GO, and the semantic similarity table to record similarity scores derived from any pair of GO terms. Based on the two tables, multifarious ways for semantic search are provided and the corresponding entries in heterogeneous biological databases in semantic terms can be expediently searched.

关键词： Gene Ontology semantic search BioDW

A Comparative Analysis of B Chromosomes and Genetic Diversity in Maize (Zea mays L.) Landraces from Southwest china

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Journal of Integrative Agriculture 2007年第10期6卷 1166-1172页

作者： YAO Qi-lun1. 2, YANG ke-cheng1. PAN Guang-tang1.and RONG Ting-zhao1.1.Maize Research Institute, Sichuan Agricultural {1., Yaan 62501., P.R.china 2 department of Life Science, Yangtze Normal {1., Fuling 408003, P.R.china [a]Maize Research Institute Sichuan Agricultural University Yaan 625014 P.R.China [b]department of Life Science Yangtze Normal University Fuling 408003 P.R.Chin

The number of B chromosomes (Bs) in 54 maize landraces from Southwest china was tested by means of cytological observations. Nine landraces with Bs were observed. A map, showing the geographic distribution of the landraces with Bs, was plotted. It was found that southeastern Sichuan Province in china was the main distribution area of the landraces with Bs in Southwest china. In order to obtain information on relationships between Bs and genetic variation, genetic diversity both among and within 1. landraces was evaluated. For each SSR marker, the number of alleles ranged from 3 to 1. with an average of 7.86, which revealed a high level of genetic diversity among maize landraces in Southwest china. Based on SSRs data, higher genetic variation was found in the landraces with 2B, and the genetic distance between the landraces with and without Bs was higher. The results together with the principal component analysis (PCA) supported the hypothesis that maize landraces in Southwest china were first introduced to the middle part of southwest Sichuan, china. At the same time, the effect of Bs on genetic variation was discussed.

关键词： Bs genetic diversity maize landraces SSR markers

Efficient computation method for two-dimensional nonlinear waves

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Acta Oceanologica Sinica 2001年第2期20卷 281-298页

作者： Wang ke ,Kang Haigui (1. State key Laboratory of Ocean & Offshore, department of Civil Engineering, Dalian university of Technology, Dalian 1.6023, china) State key Lab. of Ocean and Offshore Department of Civil Engineering Dalian University of Technology Dalian 116023 China

The theory and simulation of fully-nonlinear waves in a truncated two-dimensional wave tank in time domain are presented. A piston-type wave-maker is used to generate gravity waves into the tank field in finite water depth. A damping zone is added in front of the wave-maker which makes it become one kind of absorbing wave-maker and ensures the prescribed Neumann condition. The efficiency of numerical tank is further enhanced by installation of a sponge layer beach (SLB) in front of downtank to absorb longer weak waves that leak through the entire wave train front. Assume potential flow, the space- periodic irrotational surface waves can be represented by mixed Euler-lagrange particles Solving the integral equation at each time step for new normal velocities, the instantaneous free surface is integrated following time history by use of fourth-order Runge- Kutta method. The double node technique is used to deal with geometric discontinuity at the wave- body intersections. Several precise smoothing methods have been introduced to treat surface point with high curvature. No saw-tooth like instability is observed during the total simulation. The advantage of proposed wave tank has been verified by comparing with linear theoretical solution and other nonlinear results, excellent agreement in the whole range of frequencies of interest has been obtained.

关键词： Numerical wave tank piston-type wave-maker sponge layer beach

Expression of Hypoxia-inducible Factor-1. in Liver Tumors after Transcatheter Arterial Embolization in an Animal Model

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Journal of Huazhong university of Science and Technology(Medical Sciences) 2009年第6期29卷 776-781页

作者：梁斌郑传胜冯敢生王勇赵辉梁惠民肖恩华 department of Radiology Union Hospital Tongji Medical College Huazhong University of Science and Technology department of Radiology the Second Xiangya Hospital Xiangya School of Medicine Central South University

To examine the effect of transcatheter arterial embolization （TAE） of liver tumors on hypoxia-inducible factor-1. （HIF-1.） expression in the residual viable tumor, a total of 30 New Zealand White rabbits implanted with VX2 liver tumor were divided into 2 groups. TAE-treated group animals （n=1.） were subjected to TAE with 1.0–250 μm polyvinyl alcohol particles. Control group animals （n=1.） underwent sham embolization with distilled water. Six hours, 3 days or 7 days after TAE, the animals were sacrificed, and samples of tumor and adjacent normal liver tissue were harvested. Expression of HIF-1. protein was examined immunohistochemically. Real-time PCR was performed to examine the HIF-1. mRNA levels. Our results showed that HIF-1. protein was expressed in the VX2 tumors but not in the adjacent normal liver tissue. The HIF-1.-positive tumor cells were located predominantly at the periphery of necrotic tumor regions. The mean levels of HIF-1. protein were significantly higher in TAE-treated tumors than those in control tumors （P=0.002）. Among the three sacrificing time points, the difference in increase in HIF-1. protein was significant between the two groups at the sacrificing time point of 6 h and 3 days after TAE （P=0.020, P=0.031. respectively）, whereas no significant increase was noted 7 days after TAE （P=0.502）. In contrast, although HIF-1. mRNA was expressed in TAE-treated and control VX2 tumors, there existed no significant difference in the HIF-1. mRNA level between the two groups （P=0.372）. It is concluded that TAE of liver tumors increases the expression of HIF-1. at protein level in the residual viable tumor, which could be attributed to hypoxia generated by the procedure.

关键词： embolization hypoxia-inducible factor-1 liver neoplasms

A sequential continuous flow synthesis and purification process of calcium dibutyryladenosine cyclophosphate

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Chinese Chemical Letters 2024年第2期35卷 402-406页

作者： Liming Cao Maolin Sun Chaoming liang Lei Yang Yueyue Ma Ruihua Cheng Yanxiong {1. Wei Yu jinxing Ye Engineering Research Center of Pharmaceutical Process Chemistry Ministry of EducationSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China Shanghai No.1.Biochemical& Pharmaceutical Co. Ltd.Shanghai 200080China

Calcium dibutyryladenosine cyclophosphate is a widely used cardiovascular *** traditional batch synthesis process suffers from long reaction times,tedious operations,and unstable ***,a sequential continuous flow synthesis combined with a multistage in-line purification process of calcium dibutyryladenosine cyclophosphate was *** acylation reaction was completed in a continuous coil reactor at 1.0℃ in 20 *** the high toxic solvent pyridine was replaced by ***,the multistage in-line purification process was integrated into the homemade 3D circular cyclone-type micromixer *** with the membrane phase separators,the residence time of the purification step was 30 *** isolated yield of this sequential continuous process was 92%with 99%purity.

关键词： Flow chemistry Calcium dibutyryladenosine cyclophosphate Continuous flow synthesis In-line purification 3D circular cyclone-type micromixer chip

Density Measurement of Liquid Ni-Ta Alloys by a Modified Sessile Drop Method

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Journal of Wuhan university of Technology(Materials Science) 2005年第2期20卷 67-70页

作者：方亮 department of Applied Physics Chongqing UniversityChongqing 400044 China Satellite Venture Business Laboratory Kyushu Institute of TechnologyKitakyushu 804-8550Japan Assoc.Prof

The density of liquid Ni-Ta alloys was measured by using a modified sessile drop method. It is found that the density of the liquid Ni-Ta alloys decreases with the increasing temperature, but increases with the increase of tantalum concentration in the alloys. The molar volume of liquid Ni-Ta binary alloys increases with the increase of temperature and tantalum concentration.

关键词： Ni-Ta alloy density modified sessile drop method molar volume tantalum concentration

Stress Uniformity Process of Specimens in SHPB Test Under Different Loading Conditions of Rectangular and Half-Sine Input Waves

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Transactions of tianjin {1. 2008年第6期14卷 450-456页

作者：洪亮李夕兵刘希灵周子龙叶洲元尹土兵 School of Resources and Safety Engineering Central South University department of Civil Engineering Hunan City University

Based on the characteristics of 1. waves,the stress uniformity process in specimens under different loading conditions of rectangular and half-sine input waves was analyzed in split Hopkinson pressure bar (SHPB) *** results show that the times of an elastic wave propa-gating from one end to the other in a specimen to attain stress equilibrium,is related to input wave-forms and relative mechanical impedance between the specimen and the input/output ***-into,with the increae of the relative impedance,the times decreases under rectangular input waves loading,while it increases under half-sine input wave *** dimensionless stress value of specimen corresponding to the status of stress equilibrium increases with the increase of the rela-tive mechanical ***,the dimensionless stress value under half-sine input wave loading is significantly lower than the value under rectangular input wave loading for specimen with low mechanical impedance,and the relative differentia of the dimensionless stress values under two loading conditions decreases with the increase of the relative mechanical *** gen-eral,the forced state of specimen with relatively low mechanical impedance under half-sine input wave loading is evidently superior to the state under rectangular input wave loading in SHPB test,and the advantages of forced state under half-sine input wave loading turns weak with the increase of the relative mechanical impedance.

关键词： split Hopkinson pressure bars stress uniformity dimensionless stress half-sine input wave rectangular input wave