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Evaluating the impacts of converting grain to vegetable fields on nitrate transport in the deep vadose zone of the North China Plain

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Journal of Geographical Sciences 2025年第1期 189-212页

作者： liu Meiying MIN Leilei WU Lin zhang Yucui QI yongqing WANG Shiqin liu Binbin GENG Di SHEN Yanjun Hebei Key Laboratory of Water-Saving Agriculture Key Laboratory of Agricultural Water ResourcesCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyCAS School of Advanced Agricultural Sciences University of Chinese Academy of Sciences

Nitrate （NO3-） accumulation and transport processes in the thick vadose zone affect the evolution of the groundwater NO3-content in intensive agricultural *** land-use change （ALUC）,typically accompanied by substantial alterations in nitrogen fertilizer application and irrigation practices,is an important influencing *** study evaluated the changes in NO3-accumulation and transport in the deep vadose zone （DVZ,below the root zone）,and the groundwater NO3-content associated with ALUC from grain to vegetable fields in the North China Plain （NCP）.The ALUC from grain to vegetable resulted in nitrate–nitrogen （NO3--N） accumulation in DVZ increased by 235.5 kg ha-1m-1（163.2%） in the piedmont plain and 224.9 kg ha-1m-1（102.7%） in the central plain,*** change accelerated downward transport velocity in the DVZ (from 0.81±0.47 to 0.89±0.55 m yr-1in the piedmont plain,and from 0.24±0.12 to 0.92±0.12 m yr-1in the central plain) and increased NO3-leaching *** transport velocity and leaching fluxes resulted in chemical N-fertilizer entering the aquifer in several areas in the piedmont *** impact of the agricultural activity intensity changes,accompanied by the ALUC,on groundwater quantity and quality should be considered in similar regions.

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Off-Grid Compressed Channel Estimation with Parallel Interference Cancellation for Millimeter Wave Massive MIMO

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China Communications 2024年第3期21卷 51-65页

作者： liu Jinru Tian yongqing liu Danpu zhang Zhilong Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and ConvergenceBeijing University of Posts and TelecommunicationsBeijing100876China

Millimeter wave(mmWave)massive multiple-input multiple-output(MIMO)plays an important role in the fifth-generation(5G)mobile communications and beyond wireless communication systems owing to its potential of high ***,channel estimation has become very challenging due to the use of massive MIMO antenna ***,the mmWave channel has strong sparsity in the spatial angle domain,and the compressed sensing technology can be used to convert the original channel matrix into the sparse matrix of discrete angle *** the high-dimensional channel matrix estimation is transformed into a sparse recovery problem with greatly reduced computational ***,the path angle in the actual scene appears randomly and is unlikely to be completely located on the quantization angle grid,thus leading to the problem of power ***,multiple paths with the random distribution of angles will bring about serious interpath interference and further deteriorate the performance of channel *** address these off-grid issues,we propose a parallel interference cancellation assisted multi-grid matching pursuit(PIC-MGMP)algorithm in this *** proposed algorithm consists of three stages,including coarse estimation,refined estimation,and inter-path cyclic iterative inter-ference *** specifically,the angular resolution can be improved by locally refining the grid to reduce power leakage,while the inter-path interference is eliminated by parallel interference cancellation(PIC),and the two together improve the estimation *** results show that compared with the traditional orthogonal matching pursuit(OMP)algorithm,the normalized mean square error(NMSE)of the proposed algorithm decreases by over 14dB in the case of 2 paths.

关键词： channel estimation compressed sensing inter-path interference millimeter wave massive MIMO off-grid parallel interference cancellation

Natural Gradient Approach to Multichannel Blind Deconvolution

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Journal of Systems Engineering and Electronics 2000年第1期11卷 22-31页

作者： zhang, Liqing liu, yongqing Li, Yuanqing South China Univ of Technology Guangzhou China

In this paper we study the geometrical structures of FIR filters and their application to multichannel blind deconvolution. First we introduce a Lie group structure and a Riemannian structure on the manifolds of the FIR filters. Then we derive the natural gradients on the manifolds using the isometry of the Riemannian metric. Using the natural gradient, we present a novel learning algorithm for blind deconvolution based on the minimization of mutual information. Some properties of the learning algorithm, such as equivariance and stability are also studied. Finally, the simulations are given to illustrate the effectiveness and validity of the proposed algorithm.

关键词： Communication channels (information theory) Learning algorithms Signal filtering and prediction

Isolation and characterization of a thermophilic Bacillus shackletonii K5 from a biotrickling filter for the production of polyhydroxybutyrate

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Journal of Environmental Sciences 2014年第7期26卷 1453-1462页

作者： Yong liu Shaobin Huang yongqing zhang Fuqian Xu Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control College of Environment and EnergySouth China University of Technology State Key Laboratory of Pulp and Paper Engineering South China University of Technology The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of Education China The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions

Polyhydroxyalkanoates（PHAs） are aliphatic polyesters accumulated intracellularly by both Gram-negative and Gram-positive bacteria. However, compared to the PHAs of Gramnegative bacteria, few endotoxins（lipopolysaccharides, LPS）, which would be co-purified with PHAs and cause immunogenic reactions, are found in the PHAs produced by Gram-positive bacteria. A thermophilic Gram-positive bacterium K5, which exhibited good growth and polyhydroxybutyrate（PHB）-accumulating ability, has been isolated and characterized from a biotrickling filter designed for the removal of NOx from flue gas in a coal-fired power plant in China. Based on the biochemical characterization and 16 S rRNA gene sequence（Genbank accession no. JX437933）, the strain K5 has been identified as Bacillus shackletonii, which has rarely been reported in the literature, and this report is the first time that B. shackletonii has been found to accumulate PHB. The strain K5 was able to utilize glucose as carbon source to synthesize PHB at a broad range of temperatures（from 35 to 50 °C）, and the ideal temperature was 45 °C. The strain K5 could effectively yield PHB of up to 69.9% of its cell dry weight（CDW）（2.28 g/L） in flask experiments employing glucose as carbon source at 45 °C, followed by 56.8% and 52.3% of its CDW when using sodium succinate and glycerol as carbon source, respectively. For batch cultivation, the strain K5 was able to produce PHB of up to 72.6% of its cell dry weight（9.76 g/L） employing glucose as carbon source at 45 °C and pH 7.0.

关键词： Polyhydroxyalkanotes (PHAs) Lipopolysaccharide Thermophilic Polyhydroxybutyrate Bacillus shackletonii Batch cultivation

LA-ICPMS Zircon U-Pb Dating in the Jurassic Daohugou Beds and Correlative Strata in Ningcheng of Inner Mongolia

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 733-742页

作者： liu Yanxue liu yongqing zhang Hong Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 Key Laboratory of Insect Evolution and Environmental Changes Capital Normal University Beijing 100037 Shenyang Institute of Geology and Minerals Resources China Geological Survey Shenyang Liaoning 110032

LA-ICPMS Zircon U-Pb dating is applied to volcanic rocks overlying and underlying the Salamander-bearing bed in the Daohugou beds of Ningcheng in Inner Mongola and Reshuichang of Lingyuan and Mazhangzi of Jianping in western Liaoning. The results indicate that the youngest age of the rocks in Daohugou of Ningcheng is 158 Ma, and the oldest one is 164 Ma. Synthesized researches indicate that the salamander-bearing beds in Daohugou of Ningcheng, Reshuichang of Lingyuan and Mazhangzi of Jianping were developed in the same period. The Daohugou beds were formed in the geological age of 164-158 Ma of the middle-late Jurassic. Whilst, the Daohugou beds and its corrdative strata should correspond to the Tiaojishan Formation （or Lanqi Formation） of the middle Jurassic in northern Hebei Province and western Liaoning Province, based on the disconformity between the Daohugou beds and its overlaying beds of the Tuchengzi Formation of Late Jurassic and the Jehol Beds of early Cretaceous, and the disconformity between the Daohugou Beds and its underlying Jiulongshan Formation, which is composed of conglomerate, sandstone, shale with coal and thin coal beds.

关键词： Inner Mongolia Liaoning Daohugou Beds Zircon U-Pb dating LA-ICPMS Tiaojishan Formation Jurassic

Continuous evolution of Fermi arcs in a minimal ideal photonic Weyl medium

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Light(Science & Applications) 2024年第11期13卷 2794-2801页

作者： Yachao liu Mingwei Wang yongqing Huang Guo Ping Wang Shuang zhang State Key Laboratory of Radio Frequency Heterogeneous Integration College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China Department of Physics University of Hong KongHong KongChina Department of Electrical&Electronic Engineering University of Hong KongHong KongChina

Propagation properties of electromagnetic waves in an optical medium are mainly determined by the contour of equal-frequency states in *** photonic Weyl media,the topological surface waves lead to a unique open arc of the equal-frequency contour,called the Fermi ***,for most realistic Weyl systems,the shape of Fermi arcs is fixed due to the constant impedance of the surrounding medium,making it difficult to manipulate the surface *** we demonstrate that by adjusting the thickness of the air layer sandwiched between two photonic Weyl media,the shape of the Fermi arc can be continuously changed from convex to ***,we show that the concave Fermi-arc waves can be used to achieve topologically protected electromagnetic pulling forces over a broad range of angles in the air *** finding offers a generally applicable strategy to shape the Fermi arc in photonic Weyl media.

关键词： wave. Fermi topological

The uplifting process of the Bogda Mountain during the Cenozoic and its tectonic implication

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Science China Earth Sciences 2008年第4期51卷 579-593页

作者： ZongXiu Wang Tao Li Jin zhang yongqing liu ZongJin Ma Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China Institute of Geology China Seismological Administration Beijing 100029 China Institute of Geology Chinese Academy of Geological Sciences Beijing 1

The Tianshan Mountains have undergone its initial orogeny, extension adjusting and re-orogeny since the Late Paleozoic. The re-orogeny and uplifting process of the orogeny in the Mesozoic and Cenozoic are two of most ... 详细信息

关键词： Bogda Mountain Chain re-orogeny uplifting thermochronology fission track

Efficient quantum dot infrared solar cells with enhanced lowenergy photon conversion via optical engineering

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Nano Research 2023年第2期16卷 2392-2398页

作者： Sisi liu Ming-Yu Li Kao Xiong Jianbo Gao xinzheng Lan Daoli zhang Liang Gao Jianbing zhang Jiang Tang School of Science Wuhan University of TechnologyWuhan 430070China School of Optical and Electronic Information Wuhan National Laboratory for Optoelectronics(WNLO)Huazhong University of Science and Technology(HUST)Wuhan 430074China Department of Chemistry Brock UniversitySt.CatharinesON L2S 3A1Canada Wenzhou Advanced Manufacturing Technology Research Institute Huazhong University of Science and TechnologyWenzhou 325035China Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518057China Optics Valley Laboratory Wuhan 430074China

Infrared(IR)solar cells are promising devices for improving the power conversion efficiency(PCE)of conventional solar cells by expanding the utilization region of the sunlight spectrum to near-infrared *** solar cells based on colloidal quantum dots(QDs)have attracted extensive attention due to the widely tunable absorption spectrum controlled by dot size and the unique solution ***,the trade-off in QD solar cells between light absorption and photo-generated carrier collection has limited the further improvement of ***,we present high-performance PbS QD IR solar cells resulting from the combination of boosted light absorption and optimized carrier *** constructing an optical resonance cavity,the light absorption is significantly enhanced in the range of 1,150–1,300 nm at a relatively thin photoactive ***,the thin photoactive layer facilitates efficient carrier ***,the PbS QD IR solar cells exhibit a highly efficient photoelectric conversion in the IR region,resulting in a high IR PCE of 1.3%which is comparable to the highest value of solution-processed IR solar cells based on PbSe *** results demonstrate that constructing an optical resonance cavity is a reasonable strategy for effective conversion of photons in the devices aiming at light in a relatively narrow wavelength range,such as IR solar cells and narrow band photodetectors.

关键词： infrared solar cells PbS quantum dots optical resonance carrier extraction

Kindler syndrome protein Kindlin-1 is mainly expressed in adult tissues originating from ectoderm/endoderm

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Science China(Life Sciences) 2015年第5期58卷 432-441页

作者： ZHAN Jun YANG Mei zhang Jing GUO yongqing liu Wei zhang HongQuan Key Laboratory of Carcinogenesis and Translational Research Ministry of Education State Key Laboratory of Natural and Biomimetic Drugs Peking University Health Science Center Laboratory of Molecular Cell Biology and Tumor Biology Department of Anatomy Histology and Embryology Peking University Health Science Center Department of Thoracic Surgery Sino-Japan Friendship Hospital Department of Immunology Third Military Medical University

Mutations of integrin-interacting protein Kindlin-1 cause Kindler syndrome and deregulation of Kindlin-1 is implicated in human cancers. The Kindlin-1-related diseases are confined in limited tissue types. However, Kindlin-1 tissue distribution and the dogma that governs Kindlin-1 expression in normal human body are elusive. This study examined Kindlin-1 expression in normal human adult organs, human and mouse embryonic organs by immunohistochemical analyses. We identified a general principle that the level of Kindlin-1 expression in tissues is tightly correlated with the corresponding germ layers from which these tissues originate. We compared the expression of Kindlin-1 with Kindlin-2 and found that Kindlin-1 is highly expressed in epithelial tissues derived from ectoderm and endoderm, whereas Kindlin-2 is mainly expressed in mesoderm-derived tissues. Likewise, Kindlin-1 was also found highly expressed in endoderm/ectoderm-derived tissues in human and mouse embryos. Our findings indicate that Kindlin-1 may play an importance role in the development of endoderm/ectoderm related tissues.

关键词： Kindlin- 1 epithelial tissue ectoderm endoderm embryo