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Near-surface sand-dust horizontal flux in Tazhong-the hinterland of the Taklimakan Desert

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Journal of Arid Land 2013年第2期5卷 199-206页

作者： XingHua YANG Qing HE Mamtimin ALI wen HUO XinChun LIU Institute of Desert Meteorology China Meteorological Administration Desert Atmosphere and Environment Observation Experiment of Taklimakan Station

Tazhong is the hinterland and a sandstorm high-frequency area of the Taklimakan Desert. However, little is known about the detailed time-series of aeolian sand transport in this area. An experiment to study the sand-dust horizontal flux of near-surface was carried out in Tazhong from January to December 2009. By measur- ing the sand-dust horizontal flux throughout sixteen sand-dust weather processes with a 200-cm tall Big Spring Number Eight （BSNE） sampler tower, we quantitatively analyzed the vertical variation of the sand-dust horizontal flux. And the total sand-dust horizontal flux of different time-series that passed through a section of 100 cm in width and 200 cm in height was estimated combining the data of saltation movement continuously recorded by piezo- electric saltation sensors （Sensit）. The results indicated that, in the surface layer ranging from 0-200 cm, the inten- sity of sand-dust horizontal flux decreased with the increase of the height, and the physical quantities obeyed power function well. The total sand-dust horizontal flux of the sixteen sand-dust weather processes that passed through a section of 100 cm in width and 200 cm in height was about 2,144.9 kg, the maximum of one sand-dust weather event was about 396.3 kg, and the annual total sand-dust horizontal flux was about 3,903.2 kg. The high levels of aeolian sand transport occurred during daytime, especially from 13：00 to 16：00 in the afternoon. We try to develop a new method for estimation of the detailed time-series of aeolian sand transport.

关键词： aeolian sand transport horizontal flux saltation movement Sensit Taklimakan Desert

Chemoselective Synthesis of Novel Heterocyclic [3.3.3]Pro- pellane Derivatives via a One-pot Three-component Reaction

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Chinese Journal of Chemistry 2017年第9期35卷 1463-1468页

作者： Jing Wang Hongzhi Liu Ren wen Jie Li Songlei Zhu Department of Chemistry School of Pharmacy Xuzhou Medical University Xuzhou Jiangsu 221004 China Zhengda Tianqing Pharmaceutical Group Co. LTD Lianyungang Jiangsu 222062 China

A highly chemoselective method for the synthesis of heterocyclic [3.3.3]propellane derivatives was developed via sequential three-component reactions of acenaphthenequinone, malononitrile/cyanoacetate and a variety of 1,3-dicarbonyl compounds under mild conditions in ethanol. A plausible mechanism for this type of reaction was proposed. The value of this method was highlighted by its high selectivity, simple procedures, and good yields.

关键词： acenaphthenequinone oxa-aza[3.3.3]propellane chemoselectivity multi-component reaction

Micro-Doppler Parameter Estimation Method Based on Compressed Sensing

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Journal of Beijing Institute of Technology 2019年第2期28卷 286-295页

作者： Jiayun Chang Xiongjun Fu wen Jiang Min Xie School of Information and Electronics Beijing Institute of Technology

A micro-Doppler parameter estimation method based on compressed sensing theory is proposed in this *** micro-Doppler parameter estimation algorithm was improved for micro-motion targets with translation in this *** ideal micro-Doppler parameter estimation results were *** proposed micro-Doppler parameter estimation was compared with the traditional micro-Doppler parameter estimation *** for return signal length were analyzed with this new algorithm and its performance was also analyzed in various environments with different SNR.

关键词： feature extraction compressed sensing micro-Doppler parameter estimation

Synthesis, Crystal Structure and Luminescence of a Cadmium(Ⅱ) Coordination Polymer with 3,6-Connected rtl Topology

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Chinese Journal of Structural Chemistry 2016年第2期35卷 293-297页

作者： XUE Li-Ping SHAN Li-Li FENG wen-Jing College of Chemistry and Chemical Engineering Luoyang Normal University

A new cadmium（Ⅱ） coordination polymer,[Cd（Hcna）2]n（1）,was hydrothermally synthesized based on 5-（4-carboxyphenoxy）nicotinic acid（H2cna） organic linker.X-ray singlecrystal diffraction determination reveals that 1 crystallizes in the monoclinic P21/c space group,with a = 10.101（2）,b = 7.9139（17）,c= 15.627（3） A,β= 103.364（3）°,V= 1215.4（4） A^3,Z=2,Mr= 628.81,Dc = 1.718 Mg/m^3,μ= 0.963 mm^（-1）,F（000） = 628,the final R = 0.0177 and wR = 0.0432 for 2263 observed reflections with I 〉2σ（I）.In 1,the Cd（Ⅱ） cations are connected by nicotiniate units to form a two-dimensional（2D） layer,and it is further linked through benzoate units to form a three-dimensional（3D） ***,the structure of 1 represents a 3,6-connected 3D rtl ***,thermal stability and photoluminescent property of 1 have also been investigated.

关键词： cadmium coordination polymer crystal structure 5-(4-carboxyphenoxy)nicotinic acid rtl topology luminescence

Anomalous Kondo-Switching Effect of a Spin-Flip Quantum Dot Embedded in an Aharonov-Bohm Ring

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Communications in Theoretical Physics 2009年第11期52卷 945-948页

作者： CHEN Xiong-wen SHI Zhen-Gang SONG Ke-Hui Department of Physics and Electronic Information Science Huaihua University Huaihua 418008 China

We theoretically investigate the Kondo effect of a quantum dot embedded in a mesoscopic Aharonov-Bohm （AIR） ring in the presence of the spin flip processes by means of the one-impurity Anderson Hamiltonian. Based on the slave-boson mean-field theory, we find that in this system the persistent current （PC） sensitively depends on the parity and size of the AB ring and can be tuned by the spin-flip scattering （R）. In the small AB ring, the PC is suppressed due to the enhancing R weakening the Kondo resonance. On the contrary, in the large AB ring, with R increasing, the peak of PC firstly moves up to max-peak and then down. Especially, the PC phase shift of π appears suddenly with the proper value of R, implying the existence of the anomalous Kondo effect in this system. Thus this system may be a carldidate for quantum switch.

关键词： persistent current quantum dot Kondo effect spin-flip scattering effect

Non-small cell lung cancer in China

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Cancer Communications 2022年第10期42卷 937-970页

作者： Peixin Chen Yunhuan Liu Yaokai wen Caicun Zhou School of Medicine Tongji UniversityShanghai 200092P.R.China Department of Medical Oncology Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghai 200433P.R.China Department of Respiratory and Critical Care Medicine Huadong HospitalFudan UniversityShanghai 200040P.R.China

In China,lung cancer is a primary cancer type with high incidence and mor*** factors for lung cancer include tobacco use,family history,radiation exposure,and the presence of chronic lung *** early-stage non-small cell lung cancer(NSCLC)patients miss the optimal timing for treatment due to the lack of clinical ***-based nationwide screening programs are of significant help in increasing the early detection and survival rates of NSCLC in *** understanding of molecular carcinogenesis and the identification of oncogenic drivers dramatically facilitate the development of targeted therapy for NSCLC,thus prolonging survival in patients with positive *** the exploration of immune escape mechanisms,programmed cell death protein 1(PD-1)/programmed death-ligand 1(PD-L1)inhibitor monotherapy and PD-1/PD-L1 inhibitor plus chemotherapy have become a standard of care for advanced NSCLC in *** the Chinese Society of Clinical Oncology’s guidelines for NSCLC,maintenance immunotherapy is recommended for locally advanced NSCLC after *** immunotherapy and neoadjuvant chemoimmunotherapy will be approved for resectable *** this review,we summarized recent advances in NSCLC in China in terms of epidemiology,biology,molecular pathology,pathogenesis,screening,diagnosis,targeted therapy,and immunotherapy。

关键词： non-small cell lung cancer screening targeted therapy immunotherapy epidermal growth factor receptor(EGFR)mutation programmed cell death protein 1(PD-1) programmed deathligand 1(PD-L1) clinical trials clinical guidelines

Numerical Simulation of Non-Linear Schrodinger Equations in Arbitrary Domain by the Localized Method of Approximate Particular Solution

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Advances in Applied Mathematics and Mechanics 2019年第1期11卷 108-131页

作者： Yongxing Hong Jun Lu Ji Lin wen Chen State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering International Center for Simulation Software in Engineering and SciencesCollege of Mechanics and MaterialsHohai UniversityNanjing 211100China Nanjing Hydraulic Research Institute Hujuguan 34 RoadNanjing 210024China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210098China

The aim of this paper is to propose a fast meshless numerical scheme for the simulation of non-linear Schrodinger *** the proposed scheme,the implicit-Euler scheme is used for the temporal discretization and the localized method of approximate particular solution(LMAPS)is utilized for the spatial *** multiple-scale technique is introduced to obtain the shape parameters of the multiquadric radial basis function for 2D problems and the Gaussian radial basis function for 3D *** numerical examples are carried out to verify the accuracy and efficiency of the proposed *** with well-known techniques,numerical results illustrate that the proposed scheme is of merits being easy-to-program,high accuracy,and rapid convergence even for long-term *** results also indicate that the proposed scheme has great potential in large scale problems and real-world applications.

关键词： Schrodinger equation Localized method of approximate particular solution Shape parameters Multiple-scale technique

SELF-ASSEMBLY OF LINEAR TRIBLOCK COPOLYMERS UNDER CYLINDRICAL NANOPORE CONFINEMENTS

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Chinese Journal of Polymer Science 2013年第1期31卷 122-138页

作者： wen-juan Qiu 李士本 Yong-yun Ji Lin Xi Zhang Department of Physics Wenzhou University Department of Physics Zhejiang University

The self-assembly of linear ABC triblock copolymers under cylindrical confinements is investigated in two- dimensional space using the real-space self-consistent field theory. The effects of confinement degrees and preferential strengths on the triblock copolymer phase behaviors with special polymer parameters are first considered. On one hand, different confinement degrees cause different phase behaviors in nanopores with the neutral surfaces. Moreover, the strongly preferential surface fields can surpass the confinement degrees and volume fractions in determing the confined phase behaviors. On the other hand, in contrast, confined morphologies are more sensitive to the variations in the A-preferential surface field strength. Subsequently, the incompatibility degrees between different blocks are systematically varied under cylindrical nanopore confinements. Under cylindrical nanopore confinements, the morphologies are very sensitive to the variations in the incompatibility degrees. Meanwhile, nanopore confinements can affect order-disorder and order-order transition points in the bulk. The corresponding free, internal, and entropic energies as well as the order parameters are also quantificationally examined to deeply investigate the confined phase mechanisms, and a number of morphological transitions are confirmed to be of first-order. These findings may guide the design of novel nanostructures based on triblock copolymers by introducing confinements.

关键词： Triblock copolymers Cylindrical confinements Self-assembly Self-consistent field theory.

Stable seasonal migration patterns in giant pandas

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Zoological Research 2023年第2期44卷 341-348页

作者： Meng Wang Yong-Gang Nie Ronald R.Swaisgood Wei Wei wen-Liang Zhou Ze-Jun Zhang Gui-Ming Wang Fu-wen Wei Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Giant Panda Research San Diego Zoo Institute for Conservation ResearchEscondidoCalifornia 92027USA Department of Wildlife Fisheries and AquacultureMississippi State UniversityMississippi 39762USA

A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous *** mediated resource fluctuations may influence animal movements,enabling them to track changing resource distributions,resulting in annual migration *** conservation-dependent giant panda(Ailuropoda melanoleuca) displays seasonal movement patterns;however,the key factor driving these seasonal migration patterns remains poorly ***,we used GPS tracking collars to monitor the movements of six giant pandas over a 12-year period across different elevations,and performed statistical analysis of seasonal migration directions,routes,habitat revisitation,home range overlap,first arrival events,and *** results revealed a compelling pattern of seasonal migrations that facilitated the ability of the pandas to forage at the appropriate time and place to maximize nutritional *** results indicated that pandas utilize spatial memory to locate reliable food resources,as evidenced by their annual return to the same or similar winter and summer home ranges and the consistently maintained percentage of home range *** novel insights into giant panda foraging and movement ecology not only enhance our understanding of its ability to adapt to nutritionally poor dietary resources but also provide important information for the development of resource utilization-based protection and management strategies.

关键词： Giant panda Seasonal migration Home range Foraging ecology Spatial memory