检索结果-南通市图书馆

Chinese Chemical Letters 2004年第10期15卷 1253-1254页

作者： Hong CAI Jing zhang zheng pu zhang Yan Geng zhang Bing Lin HE State Key Laboratory of Adsorption and Separation Functional Polymeric Materials Institute of Polymer ChemistryNankai UniversityTianjin300071 The Tianjin Institute of Technological Physics Tianjin 300192

Thermosensitive hydrogels were prepared by graft polymerization of chitosan and N-isopropylacrylamide via 60 Co ?-radiation. The effects of monomer concentration and total irradiation dose on percent grafting and graf... 详细信息

关键词： γ-radiation Chitosan Graft N-isopropylacrylamide Thermosensitive

Immobilizing BINOL via Suzuki Reaction:Synthesis and Application in Catalytic Asymmetric Oxidation of Sulfide to Sulfoxide

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第7期17卷 911-912页

作者： Xiao Ya YUAN Hai Yan LI zheng pu zhang P. HODGE Key Laboratory of Functional Polymer Materials Ministry of Education Nankai University Institute of Polymer Chemistry Nankai University Tianjin 300071 Chemistry Department Manchester University M13 9PL U.K

Immobilizing chiral 1,1＇-bi-2-naphthol （BINOL） in one step onto polymer backbone via stable carbon-carbon bond through Suzuki reaction was achieved. The application of this immobilized chiral BINOL to the catalytic asymmetric oxidation of sulfide to sulfoxide exhibited good activity （up to 60% yield） and high enantioselectivity （up to 89% ee）. The immobilized chiral catalyst was very stable and could be readily reused for over 5 times without significant loss of catalytic activity and enantioselectivity.

关键词： 1,1'-Bi-2-naphthol asymmetric catalysis immobilization sulfoxide.

Enhancing microseismic/acoustic emission source localization accuracy with an outlier-robust kernel density estimation approach

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2024年第7期34卷 943-956页

作者： Jie Chen Huiqiong Huang Yichao Rui Yuanyuan pu Sheng zhang zheng Li Wenzhong Wang State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Chongqing City Construction Investment Group Co. Ltd.Chongqing 400023China Coal Geological Exploration Institute of Gansu Lanzhou 730000China

Monitoring sensors in complex engineering environments often record abnormal data,leading to significant positioning *** reduce the influence of abnormal arrival times,we introduce an innovative,outlier-robust localization method that integrates kernel density estimation(KDE)with damping linear correction to enhance the precision of microseismic/acoustic emission(MS/AE)source *** approach systematically addresses abnormal arrival times through a three-step process:initial location by 4-arrival combinations,elimination of outliers based on three-dimensional KDE,and refinement using a linear correction with an adaptive damping *** validate our method through lead-breaking experiments,demonstrating over a 23%improvement in positioning accuracy with a maximum error of 9.12 mm(relative error of 15.80%)—outperforming 4 existing *** under various system errors,outlier scales,and ratios substantiate our method’s superior *** blasting experiments also confirm the practical applicability,with an average positioning error of 11.71 m(relative error of 7.59%),compared to 23.56,66.09,16.95,and 28.52 m for other *** research is significant as it enhances the robustness of MS/AE source localization when confronted with data *** also provides a practical solution for real-world engineering and safety monitoring applications.

关键词： Microseismic source/acoustic emission(MS/AE) Kernel density estimation(KDE) Damping linear correction Source location Abnormal arrivals

Effects of two silicone resin coatings on performance of FeSiAl magnetic powder cores

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第5期31卷 1279-1288页

作者： Jia-qi Liu zheng-qu Zhu pu Wang Yi-fan Li Jing Pang Jia-quan zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao266232ShandongChina

Two silicon resins with excellent thermal stability,JH1123 and JH7102,are used as the insulated agents and binders for the gas-atomized FeSiAl powder,and corresponding magnetic powder cores(MPCs)are *** insulation capability and application prospects of the two silicon resins are evaluated by comparing the magnetic properties of the coated powder and *** scanning electron microscopy,energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy results show that uniform insulation layers are both formed on the powder ***1123 has stronger binding ability,and the JH1123-coated powder exhibits severe agglomeration,with d50(average particle size)approximately twice that of the JH7102-coated *** as-prepared MPCs exhibit outstanding soft magnetic ***,the permeability of FeSiAl@JH1123 is up to 74.0,which is 35.5%higher than that of FeSiAl@JH7102 because JH1123 can further improve the density of the *** for FeSiAl@JH7102,it has better direct current bias and lower core loss of 716.9 mW cm^(−3) at 20 mT and 1000 kHz due to its lower coercivity and greater anti-magnetic saturation ability.A comprehensive comparison shows that FeSiAl@JH1123 is suitable for medium and high frequency applications,while FeSiAl@JH7102 is more suitable for high frequency *** indicates that the use of JH1123 and JH7102 silicon resins for binding and insulated coating not only simplifies the preparation process of MPCs,but also enables the controlled production of MPCs for different applications.

关键词： FeSiAl Insulated coating Magnetic powder core Permeability Core loss

Facile surface regulation for highly efficient and thermally stable perovskite solar cells via chlormequat chloride

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第10期35卷 517-523页

作者： Bo Yang pu-An Lin Tingwei Zhou Xiaojia zheng Bing Cai Wen-Hua zhang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China School of Physical Science and Technology Southwest UniversityChongqing 400715China Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies School of Materials and EnergyYunnan UniversityKunming 650000China

Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells(PSCs).Herein,a simple and stable quaternary ammonium halide,named chlormequat chloride(i.e.,chlorinated choline chloride,CCC),is introduced to regulate the upper surface chemical environment of perovskite *** anion(Cl^(-))and cation[ClCH_(2)CH_(2)N(CH_(3))_(3)]+in CCC could effectively self-search and passivate positively and negatively charged ionic defects in per ovskites,respectively,which contributes to inhibited nonradiative recombination and reduced energy los in *** a result,the champion power conversion efficiency(PCE)of PSCs can be significantly enhanced from 22.82%to 24.07%.Moreover,the unencapsulated device with CCC modification retains 92.0%of it original PCE even subject to thermal aging at 85℃ for 2496 *** work provides guidance for the ratio nal design of functional molecules as defect passivators in PSCs,which is beneficial for the improvement in both device performance and stability.

关键词： Perovskite solarcells Quaternary ammonium halide Chlormequat chloride Surface modulation Thermal stability

Bi-Frobenius Algebra Structures on Quantum Complete Intersections

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第6期40卷 1481-1504页

作者： Hai JIN pu zhang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.China

This paper is to look for bi-Frobenius algebra structures on quantum complete intersections over field *** find a class of comultiplications,such that if√−1∈k,then a quantum complete intersection becomes a bi-Frobenius algebra with comultiplication of this form if and only if all the parameters qij=±***,it is proved that if√−1∈k then a quantum exterior algebra in two variables admits a bi-Frobenius algebra structure if and only if the parameter q=±√*** if−1/∈k,then the exterior algebra with two variables admits no bi-Frobenius algebra *** prove that the quantum complete intersections admit a bialgebra structure if and only if it admits a Hopf algebra structure,if and only if it is commutative,the characteristic of k is a prime p,and every ai a power of *** also provides a large class of examples of bi-Frobenius algebras which are not bialgebras(and hence not Hopf algebras).In commutative case,other two comultiplications on complete intersection rings are given,such that they admit non-isomorphic bi-Frobenius algebra structures.

关键词： Bi-Frobenius algebras coalgebras bialgebras Hopf algebras quantum complete intersections quantum exterior algebras

High-efficiency and flexible photonic microwave harmonic down-converter based on self-oscillation optical frequency combs

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第6期22卷 196-204页

作者： Xin zhang Tao pu Huatao Zhu Yunshan zhang Gengze Wu Jin Li Jilin zheng College of Information and Communications National University of Defense TechnologyWuhan 430010China College of Communications Engineering Army Engineering University of PLANanjing 210007China College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Photonic microwave harmonic down-converters (PMHDCs) based on self-oscillation optical frequency combs (OFCs) are interesting because of their broad bandwidth compared with plain optoelectronic oscillators. In this paper, a high-efficiency and flexible PMHDC is proposed and demonstrated. The properties of the OFC, such as the carrier-to-noise ratio (CNR),bandwidth and free spectral range (FSR), and the influence of optical injection, are investigated. The broadband OFC provides a frequency tunable and high-quality local oscillation (LO), which guarantees flexible down-conversion for the radio frequency (RF) signal. The sideband selective amplification (SSA) effect not only improves the conversion efficiency but also promotes single-sideband modulation. The conversion range can reach 100 GHz. The 12–40 GHz RF signal can be downconverted to intermediate frequency (IF) signals with a high conversion efficiency of 14.9 dB. The fixed 40-GHz RF signal is flexibly down-converted to an IF signal with the frequency from 55.4 to 2129.4 MHz. The phase noise of an IF signal at a frequency offset of 10 kHz is the same as that of the input RF signal. The PMHDC shows great performance and will find applications in radio-over-fiber (RoF) networks, electronic warfare receivers, avionics, and wireless communication systems.

关键词： frequency down-conversion optical frequency comb optical injection optoelectronic oscillation

PREPARATION AND PROPERTIES OF HIGH STRENGTH RODS FROM L-AND D,L-LACTIDE COPOLYMER

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2001年第4期19卷 351-357页

作者： Yu-shan Hu zheng-pu zhang Dong Song Dong-ren Bai Yong-mei Wang Institute of Polymer Chemistry State Key Laboratory of Functional Polymeric Materials for Adsorption and Separation, Nankai University Tianjin 300071, China Institute of Polymer Chemistry Stt. Key Lab. Funct. Polymeric M. Nankai University Tianjin 300071 China

Starling with the L- and D,L-lactide copolymer (L:DL = 9:1) [P(L-DL)LA] of M-W = 32.1 x 10(4), rods were obtained through a two stage process: (1) melt-extrusion at 155 degreesC, and (2) hot-drawing at 90 degreesC to various drawing ratios. The molecular weight of P(L-DL)LA fell to 9.3 x 10(4) as a consequence of the production process. The crystallization and molecular orientation of P(L-DL)LA developed as a result of the hot-drawing. The mechanical strengths of the rods increase with the drawing ratio; The maximum for tensile strength, bending strength, bending modulus, and shear strength are 329 MPa, 237 MPa, 8.8 GPa, and 157 MPa, respectively.

关键词： P(L-DL)LA self-reinforcement rod process bone fracture fixation

Image-Based Flow Prediction of Vocal Folds Using 3D Convolutional Neural Networks

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第2期21卷 991-1002页

作者： Yang zhang Tianmei pu Jiasen Xu Chunhua Zhou College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225127China College of Aeronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China

In this work,a three dimensional(3D)convolutional neural network(CNN)model based on image slices of various normal and pathological vocal folds is proposed for accurate and efficient prediction of glottal *** 3D CNN model is composed of the feature extraction block and regression *** feature extraction block is capable of learning low dimensional features from the high dimensional image data of the glottal shape,and the regression block is employed to flatten the output from the feature extraction block and obtain the desired glottal flow *** input image data is the condensed set of 2D image slices captured in the axial plane of the 3D vocal folds,where these glottal shapes are synthesized based on the equations of normal vibration *** output flow data is the corresponding flow rate,averaged glottal pressure and nodal pressure distributions over the glottal *** 3D CNN model is built to establish the mapping between the input image data and output flow *** ground-truth flow variables of each glottal shape in the training and test datasets are obtained by a high-fidelity sharp-interface immersed-boundary *** proposed model is trained to predict the concerned flow variables for glottal shapes in the test *** present 3D CNN model is more efficient than traditional Computational Fluid Dynamics(CFD)models while the accuracy can still be retained,and more powerful than previous data-driven prediction models because more details of the glottal flow can be *** prediction performance of the trained 3D CNN model in accuracy and efficiency indicates that this model could be promising for future clinical applications.

关键词： Vocal folds Computational fluid dynamics Machine learning 3D convolutional neural network

Bibliometric analysis and systematic review of electrochemical methods for environmental remediation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第10期144卷 113-136页

作者： Wenbin Huang Shibin Liu Tao zhang Hao Wu Shengyan pu College of Earth Sciences Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology) Chengdu 610059China College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China Key Laboratory of Biodiversity Formation Mechanism and Comprehensive Utilization of the Qinghai-Tibet Plateau in Qinghai Province Qinghai Normal UniversityXining 810008China Scientific Research Academy of Guangxi Environmental Protection Nanning 530022China

Electrochemical methods are increasingly favored for remediating polluted environments due to their environmental compatibility and reagent-saving ***,a comprehensive understanding of recent progress,mechanisms,and trends in thesemethods is currently *** of Science(WoS)databases were utilized for searching the primary data to understand the knowledge structure and research trends of publications on electrochemical methods and to unveil certain hotspots and future trends of electrochemical methods *** original data were sampled from 9080 publications in those databases with the search deadline of June 1st,*** and VOSviewer software facilitated data visualization and analysis of document quantities,source journals,institutions,authors,and *** discussed principles,influencing factors,and progress related to seven major ***,publications on this subject have experienced significant growth since *** most frequently-investigated areas in electrochemical methods included novel materials development,heavy metal remediation,organic pollutant degradation,and removal mechanism identification.“Advanced oxidation process”and“Nanocomposite”are currently trending *** major remediation mechanisms are adsorption,oxidation,and *** efficiency of electrochemical systems is influenced by material properties,system configuration,electron transfer efficiency,and power ***-Fenton exhibits significant advantages in achieving synergistic effects of anodic oxidation and electro-adsorption among the seven *** research should prioritize the improvement of electron transfer efficiency,the optimization of electrode materials,the exploration of emerging technology coupling,and the reduction in system operation and maintenance costs.

关键词： Electrochemical remediation Bibliometric analysis Heavy metals Organic pollutants Electrode materials