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Maximum relative entropy of coherence for quantum channels

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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 1-6页

作者： zhi-Xiang Jin Long-Mei Yang Shao-Ming Fei Xianqing Li-Jost zhi-Xi Wang gui-Lu Long Cong-Feng Qiao School of Physics University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Max-Planck-Institute for Mathematics in the Sciences Leipzig 04103Germany Frontier Science Center for Quantum Information Beijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China CAS Center for Excellence in Particle Physics Beijing 100049China

Based on the resource theory for quantifying the coherence of quantum channels, we introduce a new coherence quantifier for quantum channels via maximum relative entropy. We prove that the maximum relative entropy for coherence of quantum channels is directly related to the maximally coherent channels under a particular class of superoperations, which results in an operational interpretation of the maximum relative entropy for coherence of quantum channels. We also introduce the conception of subsuperchannels and sub-superchannel discrimination. For any quantum channels, we show that the advantage of quantum channels in sub-superchannel discrimination can be exactly characterized by the maximum relative entropy of coherence for quantum channels. Similar to the maximum relative entropy of coherence for channels, the robustness of coherence for quantum channels has also been investigated. We show that the maximum relative entropy of coherence for channels provides new operational interpretations of robustness of coherence for quantum channels and illustrates the equivalence of the dephasing-covariant superchannels,incoherent superchannels, and strictly incoherent superchannels in these two operational tasks.

关键词： maximum relative entropy quantum channels quantum coherence resource theory

Synthesis of dandelion-like three-dimensional nickel nanostructures via solvothermal route

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Chinese Chemical Letters 2008年第9期19卷 1123-1126页

作者： Jun Tao Tian Chun Hong Gong Lai gui Yu zhi Shen Wu zhi Jun Zhang Key Laboratory of Special Functional Materials of Ministry of Education Henan University Kaifeng 475004 China

The objectives of the present research are synthesizing three-dimensional （3D） nickel nanostructures and investigating their magnetic properties. Thus a template-free method was used to prepare 3D dandelion-like nickel nanostructures via reducing of nickel chloride with hydrazine hydrate in ethylene glycol solution at 100 ℃. The resulting Ni nanostructures were characterized by means of powder X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and selected-area electron diffraction （SAED）. And the magnetic properties of the 3D Ni nanostructures were measured as well. Results indicated that solvothermal process could be successfully used to prepare 3D dandelion-like nanostructures of Ni at a relatively mild temperature of 100℃. And the conclusions were made as follows： as-prepared Ni samples had obvious shape anisotropy and were composed of fine nanocrystallites, while they had significantly enhanced ferromagnetic properties than bulk Ni and Ni nanoparticles.

关键词： Nickel 3D nanostructures Preparation Magnetic properties

Excellent energy storage properties realized in novel BaTiO_(3)-based lead-free ceramics by regulating relaxation behavior

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Journal of Materiomics 2023年第5期9卷 910-919页

作者： Peng-Zu Ge zhi-gang Liu Xian-Xiong Huang Xin-gui Tang Zhen-Hua Tang Shui-Feng Li Qiu-Xiang Liu Yan-Ping Jiang Xiao-Bin Guo School of Physics&Optoelectric Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou510006China Guangzhou Panyu Polytechnic Guangzhou511483China

BaTiO_(3)(BT)has attracted extensive attention among advanced lead-free ferroelectric materials due to its unique dielectric and ferroelectric ***,the enormous remanent polarization and coercive field severely impede the improvement of its energy storage ***,the BaTiO_(3)e-Bi(Zn_(0.5)Hf_(0.5))O_(3)(BT-BZH)ceramics with high breakdown field strength and remarkable relaxation characteristics can be obtained by introducing the composite component BZH in BT to regulate the phase structure and grain size of the *** findings demonstrate that the improvement of energy storage performance is related to the increase of relaxation behavior.A large energy storage density(Wrec~3.62 J/cm^(3))along with superior energy storage efficiency(h~88.5%)is achieved in 0.88BT-0.12BZH relaxor ceramics only at 240 kV/*** addition,the sample suggests superior thermal stability and frequency stability within 25e115℃and 1e500 Hz,***,the outstanding chargedischarge properties with an ultrafast discharge time(100 ns),large discharged energy density(1.2 J/cm^(3)),impressive current density(519.4 A/cm^(2))and power density(31.1 MW/cm^(3))under the electric field of 120 kV/cm are achieved in studied *** excellent energy storage performance of BT-BZH ceramics provides a promising platform for the application of lead-free energy-storage materials.

关键词： BT-based ceramics Relaxor Energy storage Charge-discharge

Method of correlation function for analyzing cross-sensitivity of strain and temperature in fiber grating sensors

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Optoelectronics Letters 2007年第3期3卷 195-198页

作者： HAN gui-hua ZHANG Wei-gang Heilongjiang Engineering College Harbin 150050 China Institute of Modern Optics Nankai University Tianjin 300071 China

A novel method of correlation function for analyzing cross-sensitivity between strain and temperature is reported for the first time in this paper. Using the new method,the correlative characteristics between strain and temperature of fiber Bragg grating sensors are studied both theoretically and experimentally The experimental results accord with the theoretical calculations.

关键词：纤维光栅传感器应变温度交叉敏感问题相关函数法

Deep-detection of formation boundary using transient multicomponent electromagnetic logging measurements

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Petroleum Science 2022年第3期19卷 1085-1098页

作者： Xi-Yong Yuan Shao-gui Deng zhi-Qiang Li Xiao-Mei Han Xu-Fei Hu Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong266580China Sinopec Matrix Corporation QingdaoShandong266000China China Research Institute of Radiowave Propagation XinxiangHenan453000China China University of Petroleum—Beijing at Karamay KaramayXinjiang834000China

The maximum distance at which an electromagnetic(EM)logging while drilling(LWD)tool detects an approaching boundary is defined as the depth of detection(DOD).Ultra-deep detection capability of the transient multicomponent EM logging measurement is investigated ***,we adopt sine and cosine transform to calculate the transient multicomponent *** to the cosine transform,sine transform is more accurate in solving late-time ***,a time-domain geosignal is introduced to sense the *** show that DOD of this transient EM measurement can be up to tens of meters,including directionally ***,by studying the decay characteristics of different components with time,cross component is confirmed to decay much faster than the coaxial/coplanar components in the formation coordinate system.A pseudo-inversion is thereby proposed to determine the dip angle of anisotropic stratified *** simulation results indicate that this algebraic method can determine the true dip at some particular *** is still stable and valid even when considering random measurement ***,we establish the linear relationship between the time at which the half-point of geosignal curve appears and the distance to boundary(DTB),which would assist in the quick determination of DTB.

关键词： Time-domain Logging while drilling Formation boundary Dip angle Distance to boundary

3D rock physics template-based probabilistic estimation of tight sandstone reservoir properties

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Petroleum Science 2024年第5期21卷 3090-3101页

作者： Hao-Jie Pan Chao Wei Xin-Fei Yan Xiao-Ming Li zhi-Fang Yang zhi-Xian gui Shu-Xian Liu College of Geophysics and Petroleum Resources Yangtze UniversityWuhan430100HubeiChina Research Institute of Petroleum Exploration and Department PetrochinaBeijing100083China

Quantitative prediction of reservoir properties(e.g., gas saturation, porosity, and shale content) of tight reservoirs is of great significance for resource evaluation and well placements. However, the complex pore structures, poor pore connectivity, and uneven fluid distribution of tight sandstone reservoirs make the correlation between reservoir parameters and elastic properties more complicated and thus pose a major challenge in seismic reservoir characterization. We have developed a partially connected double porosity model to calculate elastic properties by considering the pore structure and connectivity, and to analyze these factors' influences on the elastic behaviors of tight sandstone reservoirs. The modeling results suggest that the bulk modulus is likely to be affected by the pore connectivity coefficient, while the shear modulus is sensitive to the volumetric fraction of stiff pores. By comparing the model predictions with the acoustic measurements of the dry and saturated quartz sandstone samples, the volumetric fraction of stiff pores and the pore connectivity coefficient can be determined. Based on the calibrated model, we have constructed a 3D rock physics template that accounts for the reservoir properties' impacts on the P-wave impedance, S-wave impedance, and density. The template combined with Bayesian inverse theory is used to quantify gas saturation, porosity, clay content, and their corresponding uncertainties from elastic parameters. The application of well-log and seismic data demonstrates that our 3D rock physics template-based probabilistic inversion approach performs well in predicting the spatial distribution of high-quality tight sandstone reservoirs in southwestern China.

关键词： Tight sandstones Pore structure 3D rock physics template Seismic inversion Reservoir property estimation

Performance investigation of intercooler operating in wet condition using distributed parameter model

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航空动力学报 2014年第7期29卷 1598-1605页

作者： ZHOU Ya-feng LIU gui-lin HAN Ya-hui YANG Chun-xin ZHU zhi-li School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics Shenyang Engine Design and Research Institute Aviation Industry Corporation of China School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics Mechanical Engineering Department Army Aviation Institutethe Chinese People's Liberation Army

The performance of a marine gas turbine intercooler operating in wet condition was *** intercooler was a cross-flow plate-fin heat exchanger that used air and pure water as its working fluids at the hot and cold sides,*** heat transfer performance and the water vapor condensation were investigated for a relative humidity of the inlet air that reached 100% during warship *** condensation of the water vapors increased the hot side outlet temperature by a certain amount,which could in turn influence the performance of the compressor *** condensate film thickness and the void fraction were calculated based on an annular two-phase flow *** is found that water vapor condensation in hot flow channel increases the outlet temperature with a maximum value of 7.3℃ in the case of 100% relative *** calculated liquid film thickness reaches a maximum value of 4μm,which indicates negligible thermal resistance to heat *** results of liquid film thicknesses also provide a qualitative prediction of the diameter distribution of the condensate water droplets.

关键词： intercooler wet condition plate-fin heat exchanger condensation film thickness

Electric transport properties and temperature stability of magnetoresistance of composite system between La_(8/9)Sr_(1/45)Na_(4/45)MnO_3 and Sb_2O_3

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Rare Metals 2013年第4期32卷 363-368页

作者： gui-Ying Wang Yong-gang Tang Qi-Xiang Song Ming-Yu Zhang Zhen-Sheng Peng Anhui Key Laboratory of Spintronic and Nano-materials Research School of Mechanical and Electronic Engineering Suzhou University

The samples ofLa8/9Sr1/45Na4/45MnO3 （LSNMO）/x/2（Sb2O3） were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance （MR） of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature （ρ-T） curves, mass magnetization-temperature （σ-T） curves, and magnetoresistance-temper-ature （MR-T） curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K （△T = 66 K）. MR almost remains constant in this temperature range, which favors the practical application of MR.

关键词： Electric transport property Temperaturestability of magnetoresistance Two-phase composite Perovskite manganite

Risk factors associated with early and late recurrence after curative resection of hepatocellular carcinoma: a single institution's experience with 398 consecutive patients

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Hepatobiliary & Pancreatic Diseases International 2014年第2期13卷 153-161页

作者： Zheng-gui Du Yong-gang Wei Ke-Fei Chen Bo Li Department of Liver and Vascular Surgery Liver Transplantation CenterWest China HospitalSichuan University

BACKGROUND: Surgical resection is an important curative treatment for hepatocellular carcinoma (HCC); however, some patients experience an unexpected recurrence even after hepatectomy. The present study aimed to investigate risk factors and predictive criteria for early and late recurrence of HCC after ***: A retrospective analysis of 398 Chinese patients who received curative resection for HCC was conducted. Patients were divided into three groups: without recurrence, early recurrence and late recurrence. Prognostic factors and predictive criteria for early and late recurrence were statistically analyzed. RESULTS: The cumulative recurrence-free survival rates at1, 2, 3, 4, and 5 years were 75.5%, 58.2%, 54.1%, 40.5%, and28.7%, respectively. The distribution of the time to recurrence suggested that recurrence could be divided into early phase(before 2 years; n=164) and late phase (after 2 years; n=83)Cox’s multivariate proportional hazard model analysis revealed that multiplicity of tumors (P=0.004) and venous infiltration(P=0.002) were independent risk factors associated with early recurrence. In contrast, indocyanine green retention rate at 15minutes (P=0.007), serum albumin level (P=0.045), and HBeAg status ( =0.028) proved to be significant independent adverse prognostic factors for late recurrence. Patients with at least 1of the 2 early recurrence risk factors (multiplicity of tumors ≥2and venous infiltration) or with 2 or more late recurrence risk factors are often susceptible to recurrence (P=1.36e-4 and 1.0e-6respectively).CONCLUSIONS: Early and late recurrences correlate with different risk factors and predictive criteria. Early recurrence primarily results from intrahepatic metastases, while late recurrence may be multicentric in origin.

关键词： hepatocellular carcinoma intrahepatic recurrence hepatectomy risk factors prognosis