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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 18-23页

作者： Jiarui Cai Bo Sun Huijun Wang Yi zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong Collaborative Innovation Center on forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina China Meteorological Administration Key Laboratory of Transportation MeteorologyNanjingChina Jiangsu Meteorological Observatory NanjingChina

Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical *** learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many *** this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,*** two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction *** addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance.

关键词： Groundwater depth Multi-head attention Improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia

SYNTHESIS AND CHARACTERIZATION OF COPOLYMERS BASED ON BENZOTHIADIZOLE-THIOPHENE-PHENYLENEVINYLENE

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Chinese Journal of Polymer Science 2010年第6期28卷 931-939页

作者： zheng Wang Kai-ge Meng wei Zhang Xiao-jing Yang Sheng-wei Deng Ying Li College of Chemistry Sichuan UniversityChengdu 610064China

Two novel copolymers based on benzothiadizole-thiophene-phenylenevinylene have been synthesized through palladium catalyzed triple-bond polycondensation *** copolymers exhibit good solubility in common organic solvents such as CHCl;,CH;Cl;and *** structures and properties of the two copolymers are characterized by FT-IR,;H-NMR,UV-Vis absorbance（Abs）,gel permeation chromatography（GPC）,thermal gravimetric analysis and cyclic voltammetry（CV）.The copolymers of P;and P;show absorption spectra with maximum peak at 532 nm and 573 nm in solution,*** to their monomers M;and M;,the absorption peaks of P;and P;were red-shifted by 34 nm and 54 nm *** gravimetric analysis demonstrated that the polymers were stable and little weight loss was observed below 300℃.Cyclic voltammetry experiments showed that the band gaps of the copolymers were 1.81 eV and 1.62 eV,respectively,suggesting their potential for applications as organic solar cell materials.

关键词： Benzothiadizole Triple-bond polycondensation Synthesis Organic solar cell materials

Unparallel trajectory bistatic spotlight SAR imaging

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Science in China(Series F) 2009年第1期52卷 91-99页

作者： ZHANG Lei jing wei XING MengDao BAO zheng Key Laboratory for Radar Signal Processing Xidian University Xi'an 710071 China

A new approach for unparallel trajectory bistatic spotlight SAR imaging is proposed. The approach utilizes the concept of instantaneous Doppler wavenumber and introduces two variants, the sum-range and subtraction-range, to develop the 2D frequency analytical formula. Based on the assumption of plane wavefront, the transmitting and receiving Doppler are separated and formulated via series reversion. And frequency scaling is applied to focus image. The algorithm is with high computational efficiency, and provides well focus for limited scene imaging. Simulation result confirms the validity of the approach.

关键词： unparallel trajectory bistatic SAR instantaneous Doppler wavenumber series reversion frequency scaling algorithm unparallel trajectory bistatic SAR instantaneous Doppler wavenumber series reversion frequency scaling algorithm

Removal of Cs＋ from water and soil by ammonium-pillared montmorillonite/Fe3O4 composite

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Journal of Environmental Sciences 2017年第6期29卷 12-24页

作者： Xianming zheng Junfeng Dou jing Yuan wei Qin Xiaoxi Hong Aizhong Ding College of Water Sciences Beijing Normal University

To remove cesium ions from water and soil, a novel adsorbent was synthesized by following a one-step co-precipitation method and using non-toxic raw materials. By combining ammonium-pillared montmorillonite （MMT） and magnetic nanoparticles （Fe304）, an MMT/ Fe304 composite was prepared and characterized. The adsorbent exhibited high selectivity of Cs＊ and could be rapidly separated from the mixed solution under an external magnetic field. Above all, the adsorbent had high removal efficiency in cesium-contaminated samples （water and soil） and also showed good recycling performance, indicating that the MMT/Fe304 composite could be widely applied to the remediation of cesium-contaminated environments. It was observed that the pH, solid/liquid ratio and initial concentration affected adsorption capacity. In the presence of coexisting ions, the adsorption capacity decreased in the order of Ca2 〉 M 〉 IC 〉 Na＋, which is consistent with our theoretical prediction. The adsorption behavior of this new adsorbent could be expressed by the pseudo-second-order model and Freundlich isotherm. In addition, the adsorption mecha- nism of Cs was NH4 ion exchange and surface hydroxyl group coordination, with the former being more predominant.

关键词： Ammonium-pillared montmorilloniteIron oxideMagnetic compositeAdsorptionCesium

Nanoceramic composites with duplex microstructure break the strength-toughness tradeoff

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Journal of Materials Science & Technology 2020年第23期58卷 1-9页

作者： Ji Zou Hai-Bin Ma jing-jing Liu wei-Min Wang Guo-Jun Zhang zheng-Yi Fua State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China School of Metallurgy and Materials University of BirminghamB152TTBirminghamUK China Nuclear Power Technology Research Institute Shenzhen518026China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Institute of Functional MaterialsDonghua UniversityShanghai201620China

There is a strength and fracture toughness tradeoff in nanoceramic composite. The strength varies reciprocally with the grain size whereas the toughness contributed by compressive residual stress increases with the dimension of the second phase. In this work, a novel duplex microstructure with reinforced clusters composing of nanosized grains was proposed and validated using a model system of B_(4)C-TiB_(2) ceramics densified by carbide boronizing. As-obtained ceramics exhibit excellent combined mechanical properties at room temperature, including Vickers hardness, Young's modulus, flexural strength and fracture toughness(by surface crack in flexure method) of 32.1 ± 2.7 GPa, 506.9 ± 2.0 GPa,1175 ± 71 MPa and 5.1 ± 0.4 MPa m^(0.5), respectively. Both strength and toughness are at least ~30 % higher than the counterparts with similar composition but homogenously distributed TiB_(2) grains. Graphite onion was confirmed to be an intermediate product during reactive sintering, it facilitated the grain pullout during fracture and retained the nanometric TiB_(2) grain in the cluster, both of which also contribute the toughening and strengthening mechanisms in the B_(4)C-TiB_(2) ceramics.

关键词： Borides Microstructure In-situ reaction Mechanical properties Boron carbide Ceramics

Activatable chemiluminescence probe based on four-arm PEGconjugated-pyropheophorbide-a for in vivo autofluorescence-free imaging of peroxynitrite

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Science China Chemistry 2025年

作者： Jianmei Ke Lei Ding Ronggui Lian Cheng zheng Wenjun Li Aixian zheng Yupeng Sun Ming Wu Yongyi Zeng Xiaolong Liu Maochun Hong Xiaolong Zhang The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province Mengchao Hepatobiliary Hospital of Fujian Medical University Ganjiang Innovation Academy Chinese Academy of Sciences School of Rare Earths University of Science and Technology of China College of Chemistry Fuzhou University State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Peroxynitrite（ONOO-） is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses. However, commonly used ONOO-optical imaging probes are still hampered by high background/autofluorescence（fluorescence probe）, short emission wavelength, or poor selectivity in the case of chemiluminescence. Herein,we report a facile method to prepare an activatable chemiluminescence probe（PPA-PEG） with good biocompatibility and functionality for in vivo autofluorescence-free imaging of ONOO-. The PPA-PEG consists of pyropheophorbide-a（PPA）, a typical deep red photosensitizer that acts as both the recognition and signaling element, and 4-arm poly（ethylene glycol）(4-arm PEG), which improves the biosafety and water solubility of probe. These components can self-assemble into nanoparticles（namely PPA-PEG nanoprobe） in aqueous solution. The PPA-PEG nanoprobe showed an ultra-low chemiluminescence signal before interacting with ONOO-, but exhibited good selectivity, high sensitivity and a fast response toward ONOO-. The PPAPEG was successfully applied to image cellular ONOO-changes, as well as the endogenous ONOO-changes in inflammation models and subcutaneous or orthotopic hepatocellular carcinoma（HCC） tumors models in living mice. In vitro and in vivo studies verified the good detection and imaging capabilities of PPA-PEG for peroxynitrite, demonstrating suitable tissue penetration and a high signal-to-background ratio（SBR）. Thus, our nanoprobe can serve as a valuable activatable chemiluminescence imaging tool for studying important peroxynitrite-related chemical and biological applications.

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Experimental study of phase equilibria on Co-Fe-rich side of Co-Al-Fe system

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Journal of Iron and Steel Research International 2020年第6期27卷 673-680页

作者： jing-jing Wang wei-sen zheng Xiao-gang Lu Yan-lin He Qing-rong Yao Jiang Wang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai200444China School of Materials Science and Engineering Guilin University of Electronic TechnologyGuilin 541004GuangxiChina

Despite various studies on Co-Al-Fe ternary system, its phase equilibria are still in doubt. Phase equilibria, magnetic transition and bcc_A2/bcc_B2 order-disorder transformation at the Co-Fe-rich side of the Co-Al-Fe alloys were carefully investigated by means of electron probe microanalysis (EPMA), X-ray diffraction (XRD) and differential scanning calo-rimetry. The equilibrium phases and their compositions were determined by 18 alloy samples annealed at 900, 1000, 1100 and 1200℃ for 528, 336, 168 and 96h, respectively, followed by quenching. However, by adopting the above traditional method, bcc_A2 and fcc_A1 phases are difficult to be distinguished through XRD analysis at room temperature due to the martensitic transformation of fcc_A1 phase during quenching. For this reason, high-temperature insitu XRD technique was utilized to correctly establish the phase relationships among bcc_A2, bcc_B2 and fcc_A1 phases. The phase transformation between bcc_A2 and B2 phases was determined to be second order instead of first order at temperatures higher than 900℃. The equilibrium phases and compositions were further confirmed by fabricating 16 diffusion couples together with EPMA. Meanwhile, using three-dimensional differential scanning calorimetry method, bcc_A2/B2 and ferro-/paramagnetic transi-tions were determined with high accuracy.

关键词： Co-Al-Fe system Phase equilibrium Martensitic transformation Order-disorder transition

Treatment of tannery wastewater by electrocoagulation

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Journal of Environmental Sciences 2007年第12期19卷 1409-1415页

作者： FENG jing-wei SUN Ya-bing zheng zheng ZHANG Ji-biao LI Shu TIAN Yuan-chun State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China

Treatment of tannery wastewater by electrocoagulation with low cell current （≤ 1A） and soluble electrodes （mild steel electrodes and aluminum electrodes） was studied. Compared with aluminum electrodes, mild steel electrodes were more effective for the removal of sulfide, with a removal efficiency of over 90%. But during the treatment process, black color precipitate typical to iron（Ⅱ） sulfides was produced. While aluminum electrodes were effective to eliminate the colority of the effluent, the removal efficiency of sulfide was lower than 12%. The mechanisms of the removal of chemical oxygen demand, ammonia, total organic carbon, sulfide and colority with the two soluble electrodes （mild steel and aluminum electrodes） were discussed in detail. In order to exert the predominance of diffenent types of electrodes, the tannery wastewater was treated using mild steel electrodes first followed by the filter and finally by the aluminum electrodes, the elimination rates of chemical oxygen demand, ammonia, total organic carbon, sulfide and colority were 68.0%, 43.1%, 55.1%, 96.7% and 84.3%, respectively, with the initial concentrations 2413.1 mg/L, 223.4 mg/L, 1000.4 mg/L, 112.3 mg/L and 256 dilution times, respectively. The absorbance spectra and energy consumption during electrocoagulation process were also discussed.

关键词： tannery wastewater electrocoagulation mild steel electrodes aluminum electrodes

Terahertz superconducting kinetic inductance detectors demonstrating photon-noise-limited performance and intrinsic generation-recombination noise

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Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 106-113页

作者： Qing Shi jing Li Qiang Zhi zheng Wang wei Miao Sheng-Cai Shi Purple Mountain Observatory Chinese Academy of SciencesNanjing 210034China School of Astronomy&Space Science University of Science and Technology of ChinaHefei 230026China

The development of large-format detector arrays with background-limited performance is of particular interest at the terahertz(THz) band, which is a unique band in search of our cosmic origins. With high sensitivity and being more promising in the pixel number and multiplexing technology, superconducting kinetic inductance detectors(KID) are emerging as a major choice of detectors of this type. Here we fabricate three-THz-band(0.35/0.85/1.4 THz) KIDs on a single chip from a 120-nm-thick aluminum(Al) superconducting film and measure photon-noise-limited performance and intrinsic generation-recombination noise at high(>1 p W) and low(<1 f W) optical radiation power, respectively. Their responses to blackbody(optical) radiation are proven to be purely from photons compared with the responses of two dark KIDs intentionally arranged on the same detector chip. The lowest optical noise equivalent power(NEP) reaches 6×10^(-18)W/Hz^(0.5)and the optical coupling efficiency is in the range of 49%-56% for the three KIDs, which are in good agreement with the simulation results.

关键词： terahertz kinetic inductance detectors(KID) photon-noise generation-recombination noise

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