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Spatiotemporal Bloch states of a spin–orbit coupled Bose–Einstein condensate in an optical lattice

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Chinese Physics B 2019年第5期28卷 249-255页

作者： Ya-Wen Wei Chao kong Wen-hua Hai Department of Physics and Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education and Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University

We study the spatiotemporal Bloch states of a high-frequency driven two-component Bose–Einstein condensate(BEC)with spin–orbit coupling(SOC) in an optical lattice. By adopting the rotating-wave approximation(RWA) and applying an exact trial-solution to the corresponding quasistationary system, we establish a different method for tuning SOC via external field such that the existence conditions of the exact particular solutions are fitted. Several novel features related to the exact states are demonstrated; for example, SOC leads to spin–motion entanglement for the spatiotemporal Bloch states, SOC increases the population imbalance of the two-component BEC, and SOC can be applied to manipulate the stable atomic flow which is conducive to control quantum transport of the BEC for different application purposes.

关键词： Bose–Einstein condensate spin–orbit coupling spatiotemporal Bloch state spin–motion entanglement stable atomic flow high-frequency limit

Electrochemically exfoliated WS_(2)in molten salt for sodium-ion battery anode

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Rare Metals 2023年第4期42卷 1227-1237页

作者： bei-Lei Zhang Xiang Chen Hai-Jia Zhao Hong-Wei Xie hua-Yi Yin Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education School of MetallurgyNortheastern UniversityShenyang110819China School of Resource and Environmental Science Wuhan UniversityWuhan430072China

The poor crystallinity and unstable crystal structure of tungsten disulfide(WS2)limit its application in *** this paper,a molten salt electrolysis method is proposed to intercalate metal ions into the interlayers of layered WS2 to obtain few-layer sheetlike *** effect of the molten salt system,applied constant current and electrolysis duration on the exfoliation degree of WS2 bulk has been *** results show that the products electrolyzed in molten LiCl-NaCl-KCl and NaClKCl salts under 25 mA were more transparent and thinner flakes sheets due to the uniform intercalation of Li^+and Na^+with smaller *** exfoliated WS_(2)was used as an anode material for sodium-ion batteries with a potential of 0.01-2.50 *** comparison,the WS_(2)-NaCl-25 mA electrode displays a high reversible capacity of 373 mAh·g^(-1)at0.1 A·g^(-1)after cycling for 100 cycles at the same time showing great rate and cycle *** also presents a high capacitive ratio of 90.65%at 1.0 mV·s^(-1).The molten salt electrolysis provides a new perspective on the exfoliation of layered material,while demonstrating the great potential of WS2 as an anode material for sodium-ion battery.

关键词： Tungsten disulfide Molten salt electrolysis Exfoliation Sodium-ion battery(SIB)anode

Scheme on Cross-Domain Identity Authentication Based on Group Signature for Cloud Computing

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Wuhan University Journal of Natural Sciences 2019年第2期24卷 134-140页

作者： YANG Yanyan HU Mingsheng kong Shan GONG bei LIU Xinxin School of Information Science and Technology Zhengzhou Normal University

In the cloud computing, different cloud service providers are often in different trust domains. As the traditional identity authentication mode cannot be applied to the cloud computing, the cross-domain identity authentication mechanism is needed to solve the identity authentication problem in the cloud computing. In view of the security problems in cloud computing, a cross-domain identity authentication scheme based on group signature is proposed. This scheme introduces a group of cloud service providers and users who are located in different trust domains. Any member of the group can generate the signature on behalf of the whole group, making the user access the cloud service provider in the case of privacy security. At the same time, with traceability it can track illegal operation of illegal users. In addition, the scheme uses the Chinese Remainder Theorem to integrate the message, and it can control the length of the data in the calculation process, simplifying the calculation process. It also realizes the join and revocation of group members without changing the key of other legitimate group members, and the maintenance cost of authentication schemes is low. The results show that the scheme has the advantages of anonymity, anti-counterfeit, traceability, anti-joint attack and so on. It can not only realize tracking function under the condition of guaranteeing user's privacy, but can also simplify the authentication calculation process to improve the efficiency of the cross domain identity authentication, and its performance is more suitable for large-scale cloud computing environment.

关键词： cloud computing cross-domain identity authentication group signature Chinese Remainder Theorem traceability

Etoposide Induces Mitochondria-Associated Apoptotic Cell Death in Human Gastric Carcinoma Cells

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Chemical Research in Chinese Universities 2008年第5期24卷 597-602页

作者： LI Jing-hua CHEN Yue WANG Jia-si kong Wei JIN Ying-hua Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Life Science School of Public Health Jilin University Changchun 130012 P R. China

Recent observations indicate that the resistance of apoptosis is an important process of tumor metastasis and metastases are the cause of 90% of human cancer death. Etoposide, a semisynthetic derivative of the podophyllotoxins, is a clinically used anti-cancer reagent, but the effects of it on metastatic gastric carcinoma cells are totally unknown. In this study, etoposide induced apoptotic cell death in human gastric adenocarcinoma cell line SGC-7901, derived from metastatic lymph nodes, as evidenced by the analysis of DNA fragmentation, apoptotic body formation, caspase activation, and apoptosis specific changes in cell morphology is demonstrated. The depolarization of mitochondrial membrane and the release of cytochrome c were most early events in etoposide treated SGC-7901 cells, and were followed by caspase-3 activation and PARP cleavage. Caspase-8 activation was not detected under the same condition. Thus, it was proposed that etoposide induces caspase-associated apoptotic cell death in human metastatic gastric carcinoma, which is initiated by mitochondrial cytochrome c release.

关键词： Apoptosis Caspase Cytochrome c Etoposide SGC-7901 cells

Comparison of very-high-frequency ultrasound assessment of radial arterial wall layers after first and repeated transradial coronary procedures

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Journal of Geriatric Cardiology 2017年第4期14卷 245-253页

作者： bei-bei ZHANG Yu-Jie ZHOU Jie DU Shi-Wei YANG Zhi-Jiang WANG hua SHEN Zhi-Ming ZHOU Bering Anzhen Hospital Capital Medical University Beijing Institute of Heart Lung and Blood Vessel Disease Beijing China

Background Transradial coronary procedure （TRP） traumatizes the radial artery （RA）, especially resulting in changes to arterial wall morphology. This study explored the significance of the early onset of traumatic effects to wall layers of the RA following the first TRP （FTRP） and repeat TRP （RTRP） using very-high-frequency ultrabiomicroscopy （VHFUBM）. Methods A total of 1431 patients that re- ceived TRP were divided into the FTRP group that comprised 781 patients and the RTRP group that comprised 650 patients depending on the number of procedures. Two-dimensional RA images were acquired by 30-55 MHz ultrasound one day before and one day after the pro- cedure. Results After TRP, the incidence of intimal tears, medial dissections and external elastic lamina fracture were greater in the RTRP （P 〈 0.001）. The RTRP group showed significantly thicker intimal thickness （IT）, media thickness （MT）, adventitia thickness and all complex layer thicknesses as compared with the FTRP group （P 〈 0.001）. Conclusions Multivariate linear regression analysis discovered that repeated TRP and other observations were independent predictors of increased IT in post-operative RA. VHFUBM provides an approach to study structural and histopathological injury in the wall layers of RA which showed increased trauma to the RA following RTRP.

关键词： Radial arterial wall morphology Transradial procedure Very-high-frequency ultrabiomicroscopy

Selective oxidation of methane and carbon deposition over Fe_2O_3/Ce_(1-x)Zr_xO_2 oxides

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Rare Metals 2014年第2期33卷 230-238页

作者： Xiu-Li Sang kong-Zhai Li hua Wang Yong-Gang Wei Quality Development Institute Kunming University of Science and Technology Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction Ministry of EducationKunming University of Science and Technology

A series of Fe2O3/Al2O3, Fe2O3/CeO2, Ce0.7Zr0.3O2, and Fe2O3/Ce1-xZrxO2（x = 0.1–0.4） oxides was prepared and their physicochemical features were investigated by X-ray diffraction（XRD）, transmission electron microscope（TEM）, and H2-temperature-programmed reduction（H2-TPR） techniques. The gas–solid reactions between these oxides and methane for syngas generation as well as the catalytic performance for selective oxidation of carbon deposition in O2-enriched atmosphere were investigated in detail. The results show that the samples with the presence of Fe2O3show much higher activity for methane oxidation compared with the Ce0.7Zr0.3O2solid solution,while the CeO2-contained samples represent higher CO selectively in methane oxidation than the Fe2O3/Al2O3sample. This suggests that the iron species should be the active sites for methane activation, and the cerium oxides provide the oxygen source for the selective oxidation of the activated methane to syngas during the reaction between methane and Fe2O3/Ce0.7Zr0.3O2. For the oxidation process of the carbon deposition, the CeO2-containing samples show much higher CO selectivity than the Fe2O3/Al2O3sample, which indicates that the cerium species should play a very important role in catalyzing the carbon selective oxidation to CO. The presence of the Ce–Zr–O solid solution could induce the growth direction of the carbonfilament, resulting in a loose contact between the carbon filament and the catalyst. This results in abundant exposed active sites for catalyzing carbon oxidation, strongly improving the oxidation rate of the carbon deposition over this sample. In addition, the Fe2O3/Ce0.7Zr0.3O2also represents much higher selectivity（ca. 97 %） for the conversion of carbon to CO than the Fe2O3/CeO2sample, which can be attributed to the higher concentration of reduced cerium sites on this sample. The increase of the Zr content in the Fe2O3/Ce1-xZrxO2samples could improve the reactivity of the materials for methane oxidation, but

关键词： Methane Carbon deposition Gas–solid reaction Selective oxidation of carbon Fe2O3/Ce1-xZrxO2 catalysts

Garnet and Zircon U-Pb Geochronology and Geochemistry Reveal Genesis of the Dafang Au-Pb-Zn-Ag Deposit,Southern Hunan

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 717-735页

作者： JIANG hua kong hua LIU Biao TAN Fucheng QIN Yixue huaNG Jingang ZHU Yu Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Hunan Baoshan Nonferrous Metals and Minerals Co. Ltd.ChenzhouHunan 424402China

Garnet is a primary mineral in skarn deposits and plays a significant role in recording copious mineralization and metallogenic *** study systematically investigates the geochemistry and geochronology of garnet and zircon in the Dafang Au-Pb-Zn-Ag deposit,which represents prominent gold mineralization in southern Hunan,*** samples with distinct zoning patterns and compositional variations were identified using various analytical techniques,including Backscattered Electron(BSE)imaging,Cathodoluminescence(CL)response,textural characterization,and analysis of rare-earth elements(REE),major contents,and trace element *** garnet was dated U-Pb dating,which yielded a lower intercept age of 161.06±1.93 *** age is older than the underlying granodiorite porphyry,which has a concordia age of 155.13±0.95 Ma determined by zircon U-Pb *** results suggest that the gold mineralization may be related to the concealed *** groups of garnet changed from depleted Al garnet to enriched Al garnet,and the rare earth element(REE)patterns of these groups were converted from light REE(LREE)-enriched and heavy REE(HREE)-depleted with positive europium(Eu)anomalies to medium REE(MREE)-enriched from core to rim *** different REE patterns of garnet in various zones may be attributed to changes in the fluid environment and late superposition *** development of distal skarn in the southern Hunan could be a significant indicator for identifying gold mineralization.

关键词： garnet and zircon U-Pb dating LA-ICP-MS mapping Dafang Southern Hunan

Numerical investigation of sinusoidal pulsating gas intake to intensify the gas-slag momentum transfer in the top-blown smelting furnace

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 301-314页

作者： Zhanghao Wan Shiliang Yang Desong kong Dongbo Li Jianhang Hu hua Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Southwest Copper Branch Yunnan Copper Co.Ltd.Kunming 650102China

The variation characteristics of bubble morphology and the thermal-physical properties of bubble boundary in the top-blown smelting furnace were explored by means of the computational fluid dynamics *** essential aspects of the fluid phase(e.g.,splashing volume,dead zone of copper slag,and gas penetration depth)were explored together with the effect of sinusoidal pulsating gas intake on the momentum-transfer performance between *** results illustrated that two relatively larger vortices and two smaller vortices appear in the bubble waist and below the lance,*** expansion of larger ones as well as the shrinking of smaller ones combine to cause the contraction of the bubble *** to the results of the case with a fixed gas injection velocity(V_(g)=58 m/s),the splashing volume and dead zone volume of the slag under the V_(g)=58+10sin(2πt)condition are reduced by 24.9%and 23.5%,respectively,where t represents the instant *** penetration depth and slag motion velocity of the latter are 1.03 and 1.31 times high-er than those of the former,respectively.

关键词： top-blown smelting furnace pulsed flow volume of fluid penetration depth splashing volume

Raised bed planting promotes grain number per spike in wheat grown after rice by improving spike differentiation and enhancing photosynthetic capacity

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Journal of Integrative Agriculture 2023年第6期22卷 1631-1644页

作者： DU Xiang-bei XI Min WEI Zhi CHEN Xiao-fei WU Wen-ge kong Ling-cong Crop Research Institute Anhui Academy of Agricultural SciencesHefei 230031P.R.China Rice Research Institute Anhui Academy of Agricultural SciencesHefei 230031P.R.China

The yield of wheat in wheat–rice rotation cropping systems in the Yangtze River Plain, China, is adversely impacted by waterlogging. A raised bed planting(RBP) pattern may reduce waterlogging and increase the wheat yield after rice cultivation by improving the grain number per spike. However, the physiological basis for grain formation under RBP conditions remains poorly understood. The present study was performed over two growing seasons(2018/2019and 2019/2020) to examine the effects of the planting pattern(i.e., RBP and flat planting(FP)) on the floret and grain formation features and leaf photosynthetic source characteristics of wheat. The results indicated that implementation of the RBP pattern improved the soil–plant nitrogen(N) supply during floret development, which facilitated balanced floret development, resulting in a 9.5% increase in the number of fertile florets per spike. Moreover, the RBP pattern delayed wheat leaf senescence and increased the photosynthetic source capacity by 13.9%, which produced more assimilates for grain filling. Delayed leaf senescence was attributed to the resultant high leaf N content and enhanced antioxidant metabolism. Correspondingly, under RBP conditions, 7.6–8.6% more grains per spike were recorded, and the grain yield was ultimately enhanced by 10.4–12.7%. These results demonstrate that the improvement of the spike differentiation process and the enhancement of the leaf photosynthetic capacity were the main reasons for the increased grain number per spike of wheat under the RBP pattern, and additional improvements in this technique should be achievable through further investigation.

关键词： grain number floret development photosynthetic capacity wheat grown after rice