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A facile access to mono-C-alkynylated-o-carboranes from o-carboranes and arylsulfonylacetylenes

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Chinese Chemical Letters 2022年第1期33卷 201-204页

作者： Mengyang Bai Guanyu Tao Zhenxing Liu Lili Wang Zheng Duan College of Chemistry Green Catalysis CenterInternational Phosphorus LaboratoryInternational Joint Research Laboratory for Functional Organophosphorus Materials of Henan ProvinceZhengzhou UniversityZhengzhou 450001China

A facile access to mono-C-alkynyl-o-carboranes from o-carboranes and arylsulfonylacetylenes was *** facile process tolerates a wide variety of functional groups,occurs at mild conditions in onepot procedure with short reaction *** obtained mono-C-alkynyl-o-carboranes can be easily derivatized to synthesize 1,2-difunctionalized *** work provides a useful tool for the functionalization of o-carboranes.

关键词： Alkynylation o-Carborane Arylsulfonylacetylene Transition-metal-free 1 2-Difunctionalized o-carborane

Digital simulation of 3D turbulence wind field of Sutong Bridge based on measured wind spectra

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 91-104页

作者： Hao WANG Zhou-hong ZONG Ai-qun LI Teng TONG Jie NIU Wen-ping DENG Key laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education Southeast UniversityNanjing 210096China Key laboratory of Environmental impact and Structural Safety in Engineering China University of Mining&TechnologyXuzhou 221116China

Time domain analysis is an essential implement to study the buffeting behavior of long-span bridges for it can consider the non-linear effect which is significant in long-span bridges. The prerequisite of time domain analysis is the accurate description of 3D turbulence winds. In this paper, some hypotheses for simplifying the 3D turbulence simulation of long-span cable-stayed bridges are conducted, considering the structural characteristics. The turbulence wind which is a 3D multivariate stochastic vector process is converted into four independent 1D univariate stochastic processes. Based on recorded wind data from structural health monitoring system (SHMS) of the Sutong Bridge, China, the measured spectra expressions are then presented using the nonlinear least-squares fitting method. Turbulence winds at the Sutong Bridge site are simulated based on the spectral representation method and the Fast Fourier transform (FFT) technique, and the relevant results derived from target spectra including measured spectra and recommended spectra are compared. The reliability and accuracy of the presented turbulence simulation method are validated through comparisons between simulated and target spectra (measured and recommended spectra). The obtained turbulence si-mulations can not only serve further analysis of the buffeting behavior of the Sutong Bridge, but references for structural anti-wind design in adjacent regions.

关键词： Turbulence simulation Spectral representation method Fast Fourier transform (FFT) Cable-stayed bridges Struc-tural health monitoring system (SHMS) Power spectral density

Synthesis of phosphanaphthalenes and nido-carborane fused six-membered phosphacycles

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Chinese Chemical Letters 2021年第1期32卷 194-197页

作者： Guanyu Tao Feichao Yang Lujun Zhang Yang Li Zheng Duan François Mathey College of Chemistry Green Catalysis CenterInternational Phosphorus LaboratoryInternational Joint Research Laboratory for Functional Organophosphorus Materials of Henan ProvinceZhengzhou UniversityZhengzhou 450001China

A simple method to synthesize luminescent λ^(5)-phosphanaphthalenes and zwitterionic nido-carborane fused six-membered phosphacycles was developed from the reaction of ortho-phosphinobenzoaldehydes or ortho-phosphino... 详细信息

关键词： Phosphorus λ^(5)-Phosphanaphthalenes Zwitterionic nido-Carborane Electron-deficient alkyne

Lead spall velocity of fragments of ultra-high-performance concrete slabs under partially embedded cylindrical charge-induced explosion

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Defence Technology（防务技术） 2023年第5期23卷 50-59页

作者： Yi Fan Li Chen Heng-bo Xiang Qin Fang Fang-yu Han State Key laboratory of Disaster Prevention&Mitigation of Explosion&impact Army Engineering University of PLANanjingJiangsu210007China Engineering Research Center of Safety and Protection of Explosion&impact of Ministry of Education Southeast UniversityNanjingJiangsu211189China State Key laboratory of High Performance Civil Engineering Materials NanjingJiangsu211103China

When an explosion occurs close to or partially within the face of a concrete structure, fragments are rapidly launched from the opposite face of the structure owing to concrete spalling, posing a significant risk to nearby personnel and equipment. To study the lead fragment velocity of ultra-high-performance concrete(UHPC), partially embedded explosion experiments were performed on UHPC slabs of limited thickness using a cylindrical trinitrotoluene charge. The launch angles and velocities of the resulting fragments were the determined using images collected by high-speed camera to document the concrete spalling and fragment launching process. The results showed that UHPC slabs without fiber reinforcement had a fragment velocity distribution of 0-118.3 m/s, which are largely identical to that for a normal-strength concrete(NSC) slab. In addition, the fragment velocity was negatively correlated to the angle between the velocity vector and vertical direction. An empirical Eq. for the lead spall velocity of UHPC and NSC slabs was then proposed based on a large volume of existing experimental data.

关键词： Ultra-high-performance concrete Reinforced concrete slabs Explosion Fragment velocity Blast resistance

Dynamic responses of deep underground explosions based on improved Grigorian model

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Journal of Central South University 2015年第1期22卷 323-331页

作者：陈万祥范新郭志昆王明洋 State Key laboratory of Disaster Prevention & Mitigation of Explosion & impact(PLA University of Science and Technology) State Key laboratory for Geo Mechanics & Deep Underground Engineering(China University of Mining and Technology) The Second Artillery Command Academy

It is important to investigate the dynamic behaviors of deep rocks near explosion cavity to reveal the mechanisms of deformations and fractures. Some improvements are carried out for Grigorian model with focuses on the dilation effects and the relaxation effects of deep rocks, and the high pressure equations of states with Mie-Grüneisen form are also established. Numerical calculations of free field parameters for deep underground explosions are carried out based on the user subroutines which are compiled by means of the secondary development functions of LS-DYNA9703 D software. The histories of radial stress, radial velocity and radial displacement of rock particles are obtained, and the calculation results are compared with those of U.S. Hardhat nuclear test. It is indicated that the dynamic responses of free field for deep underground explosions are well simulated based on improved Grigorian model, and the calculation results are in good agreement with the data of U.S. Hardhat nuclear test. The peak values of particle velocities are consistent with those of test, but the waveform widths and the rising times are obviously greater than those without dilation effects. The attenuation rates of particle velocities are greater than the calculation results with classic plastic model, and they are consistent with the results of Hardhat nuclear test. The attenuation behaviors and the rising times of stress waves are well shown by introducing dilation effects and relaxation effects into the calculation model. Therefore, the defects of Grigorian model are avoided. It is also indicated that the initial stress has obvious influences on the waveforms of radial stress and the radial displacements of rock particles.

关键词： underground explosion deep rock Grigorian model numerical calculation dynamic response

Temporal evolution of charged and neutral nanoparticle concentrations during atmospheric new particle formation events and its implications for ion-induced nucleation

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Frontiers of Environmental Science & Engineering 2016年第5期10卷 143-151页

作者： E. Rohan Jayaratne Buddhi Pushpawela Lidia Morawska international laboratory for Air Quality and Health Queensland University of Technology Brisbane QLD 4001 Australia

Time series of nanoparticle number concentration during new particle formation （NPF） events in the urban environment of Brisbane, Australia, showed that the formation of charged particles often occurred before that of neutral particles. We monitored 241 days during the calendar year 2012 over which NPF events were observed on 108 days. We studied the times at which the charged and neutral particle concentrations in the size range 1.8-3.2 nm reached their peak values and found that they were clearly different in 50 events with the peak neutral particle concentration lagging behind the charged particle concentration during 42 of these events with a mean time lag of 245-12 rain. While the charged particles were more likely to form before the neutral particles, once lbrmed, the growth rate of the particles did not depend on their charge. While ion-induced nucleation is not the dominant mechanism of NPF in the atmosphere, our observations suggest that the presence of ions in the atmosphere plays a role that cannot be ignored.

关键词： Charged particles Cluster ions Secondary particles Environmental pollution

Negative Thermal Expansion of GaFe(CN)_6 and Effect of Na Insertion by First-Principles Calculations

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Chinese Physics Letters 2019年第6期36卷 37-40页

作者： Meng Li Yuan Li Chun-Yan Wang Qiang Sun international laboratory for Quantum Functional Materials of Henan School of Physics and EngineeringZhengzhou University

We study the negative thermal expansion(NTE) properties and effect of Na insertion on the NTE of the framework material GaFe(CN)_6 by first-principles calculations based on density functional theory within the quasi-harmonic approximation. The calculated results show that the material exhibits NTE due to the low transverse vibrational modes of the CN groups. The modes demonstrate larger negative values of the mode Grüneisen parameters. Once Na is introduced in the framework of the material, it prefers to locate at the center of the quadrates of the framework material and binds to the four N anions nearby. As a consequence, the transverse vibrational mode of the CN group is clearly hindered and the NTE of the material is weakened. Our theoretical calculations have clarified the mechanisms of NTE and the effect of the guest Na on the NTE of the framework material.

关键词： negative thermal expansion(NTE) Na Insertion First-Principles Calculations

Surface polarization enables high charge separation in TiO_(2) nanorod photoanode

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Nano Research 2021年第11期14卷 4056-4062页

作者： Wei Ma Keke Huang Xiaofeng Wu Meng Wang Shouhua Feng State Key laboratory of Inorganic Synthesis and Preparative Chemistry NMAC International Joint LaboratoryCollege of ChemistryJilin UniversityChangchun130012China

Poor charge separation efficiency of semiconductors often stands in the way of photoelectrochemical (PEC) water splitting realization. In this report, a surface polarized TiO_(2) photoanode is obtained via −OH moiety decoration, which achieves a fundamentally improved charge separation efficiency of about 94% at 1.23 VRHE. Detailed data shows that these hydroxyls with electric dipoles polarize the surface, inducing substantial electric field in the surface region, and elevating band edges so as to form a homojunction within TiO_(2). Such serves as the direct driving force for the photogenerated charge separation and migration. Moreover, these hydroxyls also facilitate water oxidation kinetics. Without typical doping or cocatalyst, surface polarized TiO_(2) photoanode delivers a considerably increased photocurrent density of about 1.41 mA·cm^(−2) at 1.23 VRHE (AM 1.5 G) and a cathodic shift on onset potential over 200 mV. This report highlights new opportunities to modulate charge separation by surface polarization for the construction of robust photoanodes.

关键词： TiO_(2)nanorod hydroxyls surface polarization charge separation photoelectrochemical water splitting

Seismic behavior of outrigger truss-wall shear connections using multiple steel angles

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 197-208页

作者： Li Xian Wang Wei Lü Henglin Zhang Guangchang State Key laboratory for Geomechanics & Deep Underground Engineering China University of Mining and Technology Jiangsu Key laboratory of Environmental impact and Structural Safety in Civil Engineering School of Mechanics and Civil Engineering China University of Mining and Technology

An experimental investigation on the seismic behavior of a type of outrigger truss-reinforced concrete wall shear connection using multiple steel angles is presented. Six large-scale shear connection models, which involved a portion of reinforced concrete wall and a shear tab welded onto a steel endplate with three steel angles, were constructed and tested under combined actions of cyclic axial load and eccentric shear. The effects of embedment lengths of steel angles, wall boundary elements, types of anchor plates, and thicknesses of endplates were investigated. The test results indicate that properly detailed connections exhibit desirable seismic behavior and fail due to the ductile fracture of steel angles. Wall boundary elements provide beneficial confinement to the concrete surrounding steel angles and thus increase the strength and stiffness of connections. Connections using whole anchor plates are prone to suffer concrete pry-out failure while connections with thin endplates have a relatively low strength and fail due to large inelastic deformations of the endplates. The current design equations proposed by Chinese Standard 04G362 and Code GB50011 significantly underestimate the capacities of the connection models. A revised design method to account for the influence of previously mentioned test parameters was developed.

关键词： anchor truss suffer welded reinforced stiffness tensile desirable properly frames