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State to State Photodissociation Dynamics of Vibrationally Excited D2O in B Band

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： shan-yu Han Lin-sen zhou Dai-qian Xie Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China

The state-to-state photodissociassion dynamics for the B band of D2O have been explored from quantum dynamical calculations including the electronic ?X and ?B states. The calculations were carried out using a Chebyshev real wave packet method. The calculated absorption spectra, product state distributions, and branching ratios from different initial vibrational states show different dynamic features, due to the different shapes of the vibrational wavefunctions. The initial bending mode (0,1,0) generates two lobes with a shallow minimum on the absorptionspectrum and a slight inverted vibrational population of OD(?X) product at high total energies. The rotational state distributions of OD(?X, v=0) product are highly inverted and depend weakly on the initial state and total energy. On the other hand, the ro-vibrational distributions of OD(?A) product strongly oscillate with the total energy, which are dominated by the long-living resonances and depend sensitively on the potential surfaces. The antisymmetric stretching mode (0,0,1) has large OD(?A)/OD(?X) branching ratios at high total energies, which indicates that the B band dissociation proceeds mainly via the adiabatic pathway in some cases.

关键词： Photodissociation D2O Vibrationally excited state Conical intersection Quantum dynamics

A topology control algorithm based on D-region fault tolerance

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Science China(Information Sciences) 2013年第7期56卷 33-41页

作者： SUN RuoZi WANG yue YUAN Jian shan XiuMing REN Yong Department of Electronic Engineering Tsinghua University Deparment of Applied Mathematics Harbin University of Science and Technology

In a wireless network, node failure due to either natural disasters or human intervention can cause network partitioning and other communication problems. For this reason, a wireless network should be fault tolerant. At present, most researchers use k-connectivity to measure fault tolerance, which requires the network to be connected after the failure of any up to k-1 nodes. However, wireless network node failures are usually spatially related, and particularly in military applications, nodes from the same limited area can fail together. As a metric of fault-tolerance, k-connectivity fails to capture the spatial relativity of faults and hardly satisfies the fault tolerance requirements of a wireless network design. In this paper, a new metric of fault-tolerance, termed D-region fault tolerance, is introduced to measure wireless network fault tolerance. A D-region fault tolerant network means that even after all the nodes have failed in a circular region with diameter D, it still remains connected. Based on D-region fault tolerance, we propose two fault-tolerant topology control algorithms--the global region fault tolerance algorithm (GRFT) and the localized region fault tolerance algorithm (LRFT). It is theoretically proven that both algorithms are able to generate a network with D-region fault tolerance. Simulation results indicate that with the same fault tolerance capabilities, networks based on both GRFT and LRFT algorithms have a lower transmission radius and lower logical degree.

关键词： fault tolerance connectivity spatial relativity topology control

Power allocation in cooperative MIMO systems under individual power constraints

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 1-6页

作者： YANG shan CUI Qi-mei XU yue-qiao LUO Yuan Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

allocation （PA） plays an important role in capacity improvement for cooperative multiple-input multipleoutput （Co-MIMO） systems. Many contributions consider a total power constraint （TPC） on the sum of transmit power from all nodes in addressing PA problem. However, in practical implementations, each transmit node is equipped with its own power amplifier and is limited by individual power constraint （IPC）. Hence these PA methods under TPC are not realizable in practical systems. Meanwhile, the PA problem under IPC is essential, but it has not been studied. This paper extends the traditional non-cooperative water-filling PA algorithm to IPC-based Co-MIMO systems. Moreover, the PA matrix is derived based on the compound channel matrix from all the cooperative nodes to the user. Therefore, the cooperative gain of the IPC-based Co-MIMO systems is fully exploited, and further the maximal instantaneous capacity is achieved. Numerical simulations validate that, under the same IPC conditions, the proposed PA scheme considerably outperforms the non-cooperative water-filling PA and uniform PA design in terms of ergodic capacity.

关键词： power allocation cooperative MIMO individual power constraint ergodic capacity

Bunch-by-bunch longitudinal phase monitor at SSRF

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Nuclear Science and Techniques 2018年第8期29卷 149-154页

作者： Yi-Mei zhou Han-Jiao Chen shan-shan Cao Yong-Bin Leng shanghai Institute of Applied Physics Chinese Academy of Sciences shanghai Synchrotron Radiation Facility Chinese Academy of Sciences

Beam signals captured from a button-type pickup contain multidimensional information including the bunch charge,transverse position,bunch length,and longitudinal phase.A bunch phase monitor,which retrieves longitudinal phase information from a pickup signal at a bunch-by-bunch rate,has been developed at the shanghai Synchrotron Radiation *** paper introduces the basic principles,system setup,data processing method,and preliminary experimental results of this *** systematic measurement error introduced by the limited system bandwidth,bunch length,and bunch charge variation was studied using simulation *** random measurement uncertainty was evaluated using experimental beam *** experimental result shows that the longitudinal phase resolution of this system is better than 1.0 *** first application,measuring the relationship between the longitudinal phase and bunch charge to determine the energy loss factor,was implemented,and the preliminary result is also discussed.

关键词：监视器 SSRF 数据处理方法同步加速器试验性信号信息系统

β-Phase Crystallization of Poly(vinylidene fluoride) in Poly(vinylidene fluoride)/Poly(ethyl methacrylate) Blends

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Chinese Journal of Polymer Science 2019年第1期37卷 94-100,4-7页

作者： Zi-Jie Huang Jing Jiang Gi Xue Dong-shan zhou Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Key Laboratory of High Performance Polymer Materials and Technology and The State Key Laboratory of Coordination Chemistry Nanjing University School of Physical Science and Technology Xinjiang Key Laboratory and Phase Transitions and Microstructures in Condensed Matters Yili Normal University

The nature of the crystalline phase of poly(vinylidene fluoride)(PVDF) in compatible blends with poly(ethyl methacrylate)(PEMA) was investigated by using X-ray diffraction(XRD), infrared microscopy(IR) and differential scanning calorimetry(DSC). The βphase of PVDF was observed after quenching from the melt and further annealing above the glass transition temperature over a composition range. The PVDF/PEMA blend with weight ratio of 3:2 has formed higher content of PVDF β crystals than others. By taking advantage of fast cooling rate of ultrafast differential scanning calorimeter(UFDSC), the quenching process of blends was modeled and tested simultaneously, and the melting behavior of β crystals in all blends was investigated. Three types of crystallization behavior of βphase PVDF in blends were found after quenching-annealing at different temperatures.

关键词： β-Crystal of PVDF Mesophase PVDF/PEMA blend Ultra-fast scanning calorimetry

Theoretical and Experimental Study on Plug Shape Parameter of Press Piercing Mill

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Journal of Iron and Steel Research International 2003年第4期10卷 33-37页

作者： SUN Deng-yue DU Feng-shan XU Shi-min Yanshan University

The characteristics of some elements in inoculant were analyzed. The effect of the morphology of instantaneous inoculant on its melting velocity was studied. When the inoculants pass through the same sieve number, the volume and the ratio of surface area to volume are different. It is evident from the theoretical analysis and experiment under some conditions that the melting velocity of inoculant depends on the morphology of inoculant. The morphology of inoculant during production should be controlled carefully.

关键词： instantaneous inoculant morphology melting velocity melted iron

A Comparison of Shale Gas Fracturing Based on Deep and Shallow Shale Reservoirs in the United States and China

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 471-507页

作者： Qixing Zhang Bing Hou Huiwen Pang shan Liu yue Zeng State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China Key Laboratory of Petroleum Engineering Ministry of EducationChina University of Petroleum(Beijing)Beijing102249China

China began to build its national shale gas demonstration area in *** central exploration,drilling,and development technologies for medium and shallow marine shale reservoirs with less than 3,500m of buried depth in Changning-Weiyuan,Zhaotong,and other regions had *** this study,we macroscopically investigated the development history of shale gas in the United States and China and compared the physical and mechanical conditions of deep and shallow *** comparative results revealed that themain reasons for the order-ofmagnitude difference between China’s annual shale gas output and the United States could be attributed to three aspects:reservoir buried depth,reservoir physical and mechanical properties,and engineering technology *** current engineering technology level of China could not meet the requirements of increasing production and reducing costs for deep shale gas reservoirs;they had reached the beneficial threshold development stage and lacked the capacity for large-scale commercial *** identified several physical and mechanical reasons for this threshold development *** shale reservoirs were affected by the bedding fracture,low brittleness index,low clay mineral content,and significant areal differences,as well as by the transformation from elasticity to plasticity,difficulty in sanding,and high mechanical and strength ***,they were accompanied by six high values of formation temperature,horizontal principal stress difference,pore pressure,fracture pressure,extension pressure,and closure *** key to deep shale gas horizontal well fracturing was to improve the complexity of the hydraulic fracture network,formadequate proppant support of fracture surface,and increase the practical stimulated reservoir volume(SRV),which accompanied visual hydraulic discrete network *** this basis,we proposed several ideas to improve China’s deep shale gas development involving advanced technolo

关键词： Deep and shallow shale in the United States and China physical and mechanical properties multistage/multicluster fractures network monitoring soak well and flow back

Effective degradation of tetracycline by mesoporous Bi2WO6 under visible light irradiation

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Frontiers of Environmental Science & Engineering 2016年第2期10卷 211-218页

作者： Xiaolong CHU Guoqiang shan Chun CHANG Yu FU Longfei yue Lingyan ZHU College of Environmental Science and Engineering Nankai University Tianjin 300071 China

Bi2WO6 was synthesized with a hydrothermal method at different pHs and used for the degradation of tetracycline （TC） in water. The mesoporous BiEWO6 prepared at pH 1 （BWO-1） displayed the highest adsorption and degradation capacity to TC due to its large surface area and more efficient capacity to separate photogenerated electrons and holes. 97% of TC at 20 mg · L-1 was removed by BWO-1 at 0.5 g-L-1 after 120min irradiation under simulated solar light. Only 31% of the total organic carbon （TOC） was removed after 360 min irradiation although the TC removal reached 100%, suggesting that TC was mainly transformed to intermediate products rather than completely mineralized. The inter- mediates were identified by high-performance liquid chromatography-time of flight-mass spectrometry （HPLC-TOF-MS） and possible photodegradation path- ways were proposed.

关键词： Bi2W06 hydrothermal synthesis tetracycline(TC) photocatalysis

A New β-Carboline Alkaloid and a New Derivate of Isoferulic Acid from Anemone altaica

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Chinese Chemical Letters 2005年第11期16卷 1484-1486页

作者： Zhong Jie ZOU yue Sheng DONG Jun shan YANG Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094

A new β-carboline alkaloid, 4-（9H-β-carbolin-1-yl）-4-oxobutyric acid and a new derivate of isoferulic acid, （E）-3-（3-hydroxy-4-methoxyphenyl）acrylic acid carboxymethyl ester, were isolated from the roots of An... 详细信息

关键词： Anemone altaica β-carboline alkaloid isoferulic acid derivate.