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A Simple Empirical Formula for Predicting the Ultimate Strength of Ship Plates with Elastically Restrained Edges in Axial Compression

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China Ocean Engineering 2020年第4期34卷 571-580页

作者： LIU Cong zhang Shi-lian State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

An investigation is conducted on the static ultimate limit state assessment of ship hull plates with elastically restrained edges subjected to axial *** material and geometric non-linearities were considered in finite element(FE)*** initial geometric imperfection of the plate was considered,while the residual stress introduced by welding was not *** ultimate strength of simply supported ship hull plates compared well with the existing empirical formula to validate the correctness of the applied boundary conditions,initial imperfection and mesh *** extensive FE calculations on the ultimate strength of ship hull plates with elastically restrained edges are *** a new simple empirical formula for plate ultimate strength is developed,which includes the effect of the rotational restraint stiffness,rotational restraint stiffness,and aspect *** applying the new formula and FE method to ship hull plates in real ships,a good coincidence of the results between these two methods is obtained,which indicates that the new formula can accurately predict the ultimate strength of ship hull plates with elastically restrained edges.

关键词： ship hull plate ultimate strength axial compression elastically restrained edges empirical formula

Increased ammonification,nitrogenase,soil respiration and microbial biomass N in the rhizosphere of rice plants inoculated with rhizobacteria

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Journal of Integrative Agriculture 2021年第10期20卷 2781-2796页

作者： zhang Jun-hua HUANG Jing Sajid HUSSAIN zhu lian-feng CAO Xiao-chuang zhu Chun-quan JIN Qian-yu zhang Hui State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006P.R.China Agricultural Resources and Environment Institute Jiangsu Academy of Agricultural SciencesNanjing 210014P.R.China

Azospirillum brasilense and Pseudomonas fluorescens are well-known plant growth promoting ***,the effects of *** and *** on the N cycles in the paddy field and rice plant growth are little *** study investigated whether and how *** and *** contribute to the N transformations and N supply capacities in the rhizosphere,and clarified the effects of *** and *** on the N application rate in rice *** with *** and *** coupled with N application rate trials were conducted in the paddy field in 2016 and *** inoculations of rice seedlings included four treatments:sterile saline solution(M_(0)),***(M_(b)),***(M_(p)),and co-inoculation with a mixture of *** and ***(M_(bp)).The N application rate included four levels:0 kg N ha^(–1)(N_(0)),90 kg N ha^(–1)(N_(90)),180 kg N ha^(–1)(N_(180)),and 270 kg N ha^(–1)(N_(270)).The results indicated that the M_(bp) and M_(p) treatments significantly enhanced the ammonification activities in the rhizosphere compared with the M_(0) treatment,especially for higher N applications,while the Mbp and M_(b) treatments greatly enhanced the nitrogenase activities in the rhizosphere compared with the M_(0) treatments,especially for lower N *** brasilense and *** did not participate in the nitrification processes or the denitrification processes in the *** soil respiration rate and microbial biomass N were greatly affected by the interactions between the rhizobacteria inoculations and the N fertilizer *** the M_(bp) treatment,N supply capacities and rice grain yields showed no significant differences among the N_(90),N_(180),and N_(270) *** N application rate in the study region can be reduced to 90 kg N ha^(–1) for rice seedlings co-inoculated with a mixture of *** and ***.

关键词： N transformation paddy soil plant growth promoting rhizobacteria rice productivity

Soliton solutions for a two-component generalized Sasa-Satsuma equation

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Communications in Theoretical Physics 2023年第7期75卷 33-47页

作者： lian-li Feng Zuo-nong zhu School of Mathematical Sciences Shanghai Jiao Tong University80 Dongchuan RoadShanghai200240China

As is well known,the Sasa-Satsuma equation is an important integrable high order nonlinear Schr?dinger *** this paper,a two-component generalized Sasa-Satsuma(g SS)equation is *** construct the n-fold Darboux transformation for the two-component g SS *** on the Darboux transformation,we obtain some interesting solutions,such as a breather soliton solution,kink solution,anti-soliton solution and a periodic-like solution.

关键词： equation solution equation

Synthesis,Crystal Structure and Luminescent Properties of a 1D Loop-chain Coordination Polymer [Ag(3,3-pybz)(3,3-Hpybz)]_n

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1767-1772页

作者： TANG Long FU Feng WEI Qing-Bo WANG Sheng-Wen zhang zhu-lian Yan'an University Department of Chemistry and Chemical EngineeringShaanxi Key Laboratory of Chemical Reaction Engineering

A new coordination polymer, [Ag（3,3-pybz）（3,3-Hpybz）]n （1, 3,3-Hpybz = 3-pyri- din-3-yl-benzoic acid）, has been synthesized and characterized by elemental analysis, IR spectra, PXRD, and single-crystal X-ray diffraction. In complex 1, the Ag（1）ions are linked by the paired 3,3-pybz ligands to generate an infinite 1D loop chain, and further through π-π stacking interactions to form a 2D supramolecular architecture. Crystal data for 1： triclinic, space group P1, a = 10.2635（17）, b = 10.3041（12）, c = 10.8060（13） A, V= 1679.1（5）A3, α = 62.028（11）, β = 80.325（15）, γ = 78.738（14）°, Z = 2, C24H17AgN2O4, Mr = 505.27, Dc= 1.698 g/cm3, μ= 1.058 mm--, F（000） = 506, S = 1.012 and T = 293（2） K. The final R = 0.0293 and wR = 0.0667 for 3435 observed reflections with I〉 2a（/）, and R = 0.0350 and wR = 0.0688 for all data.

关键词： Ag(I) compound crystal structure luminescent properties

BoxCox multi-output linear regression for 10.7 cm solar radio flux prediction

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Research in Astronomy and Astrophysics 2021年第4期21卷 225-234页

作者： Rui-Fei Cui Ya-Guang zhu Huan zhang Ri-Wei zhang Hong-Yu Zhao Zheng-lian Li State Key Laboratory of Astronautic Dynamics Xi’an 710043China Beijing Information and Communication Research Center Beijing 100840China

We consider the problem of predicting the mid-term daily 10.7 cm solar radio flux(F10.7),a widely-used solar activity index.A novel approach is proposed for this task,in which BoxCox transformation with a proper parameter is first applied to make the data satisfy the property of homoscedasticity that is a basic assumption of regression models,and then a multi-output linear regression model is used to predict future F10.7 *** experiment shows that the BoxCox transformation significantly improves the predictive performance and our new approach works substantially better than the prediction from the US Airforce and other alternative methods like Auto-regressive Model,Multi-layer Perceptron,and Support Vector Regression.

关键词： Sun:radio radiation methods:data analysis methods:statistical

Geochemical Forms of Phosphorus in Sediments of Three Large, Shallow Lakes of China

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Pedosphere 2006年第6期16卷 726-734页

作者： zhu Guang-Wei QIN Bo-Qiang zhang Lu LUO lian-Cong Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

A sequential extraction method for the fractionation of phosphorus （P） in lake sediments was used to analyze phos- phorus fractions of sediments taken from three large, shallow. eutrophic freshwater lakes of China-Talhu Lake. Chaohu Lake, and *** Lake. All three lakes are located in the lower reaches of the Changjiang River （Yangtze River）. In Taihu Lake and Chaohu Lake, algae blooms occurred every year, while Longgan Lake was a macrophyte-dominated lake. Results showed that exchangeable phosphorus fractions were much higher in the eutrophic lake sediments than in the macrophyte-flourishing lake sediment. Also, the ratio of Fe：P in the sediments of the algae-predomlnant lakes was generally much lower than that in the macrophyte-predominant lakes. Thus, the geochemical fractions of phosphorus in sediments had a closer relationship with the type of aquatic vegetation.

关键词： algal bloom macrophyte phosphorus sediment shallow lakes

使用合规农药能确保农产品“地头”质量安全吗?——基于豇豆农户的扎根理论分析

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海南大学学报（人文社会科学版） 2025年第1期43卷 119-128页

作者：樊孝凤张娇朱月季海南大学国际商学院海南海口570228

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析... 详细信息

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析了访谈资料。研究发现:农户施药环节是一个复杂的行为选择过程,即使施用合规农药也不能确保农产品在产地的质量安全。在合规农药视角下影响农户施药行为选择的最重要因素是信息渠道,其次是农产品质量安全管理的政策强度、农产品市场价格和农村劳动用工成本。同时,邻里效应在农户施药行为选择中的作用越来越弱。在此基础上提出,要增加农户用药信息的有效供给渠道,加强农产品质量安全的全面检测,坚持为农户提供形式多样的有针对性的有效培训,增加重要食用农产品质量安全关键技术供给与推广,加强农产品“优质优价”市场建设的政策建议,并进一步指出海南自贸港建设和RECP协议实施背景下提升海南农产品质量安全水平的紧迫性。

关键词：合规农药施药行为农产品质量安全扎根理论

维普期刊数据库博看期刊

Synthesis and Crystal Structure of a Complex of Melamine with Benzoic Acid

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Chemical Research in Chinese Universities 2008年第4期24卷 396-400页

作者： zhang Xiu-lian Department of Chemistry Guangdong Institute of Education Guangzhou 510310 P. R. China

A new complex of melamine（MA） with benzoic acid（HBA） was prepared, affording [（HMA＋）（BA-）]-2H2O. Each HBA molecule is deprotonated and one triazine nitrogen atom of MA is protonated. The adjacent HMA＋ cations are related via an inverse center to form ribbons with a pair of N--H…N hydrogen bonds. COO- groups of BA- anions are hydrogen bonded to alternate sides of the （HMA＋）∞ ribbons to generate indention ID tapes, which are extended into a 3D structure via N--H…O- and N--H…OW hydrogen bonds and π-π stacking interactions. Predominant patterns of the hydrogen bond present in the complex are anion/water and amino/water tape structures. The hydrogen-bonding patterns consist of alternate 6, 10-membered rings sharing two edges. Infrared（IR） spectroscopy conforms that proton transfer has taken place in the complex.

关键词： Hydrogen bond Crystal structure Melamine Benzoic acid

A General Strategy for Ordered Carrier Transport of Quasi‑2D and 3D Perovskite Films for Giant Self‑Powered Photoresponse and Ultrahigh Stability

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Nano-Micro Letters 2023年第8期15卷 128-140页

作者： Fei zhu Gang lian Deliang Cui Qilong Wang Haohai Yu Huaijin zhang Qingbo Meng Ching‑Ping Wong State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100People’s Republic of China Key Laboratory for Special Functional Aggregated Materials of Education Ministry School of Chemistry&Chemical EngineeringShandong UniversityJinan 250100People’s Republic of China Key Laboratory for Renewable Energy Chinese Academy of Sciences(CAS)BeijingPeople’s Republic of China Key Laboratory for New Energy Materials and Devices Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsCASBeijing 100190People’s Republic of China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Organic–inorganic hybrid perovskite materials have been focusing more attention in the field of self-powered photodetectors due to their superb photoelectric ***,a universal growth approach is required and challenging to realize vertically oriented growth and grain boundary fusion of 2D and 3D perovskite grains to promote ordered carrier transport,which determines superior photoresponse and high ***,a general thermal-pressed(TP)strategy is designed to solve the above issues,achieving uniaxial orientation and single-grain penetration along the film thickness *** constructs the efficient channel for ordered carrier transport between two *** of the improved crystal quality and lower trap-state density,the quasi-2D and 3D perovskite-based self-powered photodetector devices(with/without hole transport layer)all exhibit giant and stable photoresponse in a wide spectrum range and specific wavelength *** the MAPbI_(3)-based self-powered photodetectors,the largest R_(λ) value is as high as 0.57 A W^(−1)at 760 nm,which is larger than most reported ***,under laser illumination(532 nm),the FPEA_(2)MA_(4)Pb_(5)I_(16)-based device exhibits a high responsivity(0.4 A W^(−1)) value,which is one of the best results in 2DRP self-powered *** addition,fast response,ultralow detection limit,and markedly improved humidity,optical and heat stabilities are clearly demonstrated for these TP-based devices.

关键词： Perovskites Thermal-pressed strategy Uniaxial orientation Self-powered photodetectors Stability