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Nano Research 2023年第7期16卷 8522-8532页

作者： Yue Wu Shujuan tan Taichen Zhang Ming Zhou Gang Fang Guangbin ji School of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Alkali and Co^(2+)co-modulation has seldom been investigated as a prospective strategy to achieve high-efficient microwave absorbing(MA)*** this work,a new alkali and Co ion exchange co-modulation strategy was first reported,leading to broadband MA capacity through simultaneous manipulating multiple factors,such as composition,micromorphology,and heterogeneous *** enhancements in impedance matching and magnetic-dielectric loss were synergistically ***,the optimized FeCo alloy@porous carbon(FPC)nanocomposite with the alkali regulation delivered an effective absorption bandwidth(EAB)of 6.72 GHz,making it the merely single FeCo-based metal-organic framework derived FPC absorber with a low filler content of 15 wt.%.Interestingly,the nanocomposites by ion exchange strategy realized the switchable“on/off”states on electromagnetic ***,the radar cross-section(RCS)reduction value of the products reached 25.6 dB·m^(2) under the incident angle of 0°.In brief,this work not only offers the special role of alkali and Co^(2+)co-modulation in composition regulation,structure design,and MA capacity,but also provides a reliable strategy to develop smart nano-absorbers to cope with electromagnetic pollution issues.

关键词： microwave absorption alkali regulation ion exchange strategy switchable on/off mode nano-absorbers

Controllable heterogeneous interfaces and dielectric regulation of hollow raspberry-shaped Fe_(3)O_(4)@rGO hybrids for high-performance electromagnetic wave absorption

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Journal of Materials Science & Technology 2023年第20期151卷 10-18页

作者： Yuhan Wu Shujuan tan Puyu Liu Yan Zhang Peng Li Guangbin ji College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Heterogeneous interface engineering is closely related to the structural design of electromagnetic absorbers;thus,the interface control through structural design is a considerable approach to optimize the electromagnetic wave absorption(EWA)***,the 3D hierarchical structure composites composed of two-dimensional reduced graphite oxide(rGO)and hollow raspberry Fe_(3)O_(4) nanoparticles was successfully fabricated by a simple pyrolysis and self-assembly *** specific structure enriches the characteristics of interface polarization and dipole polarization,which further induces significant EWA *** adjusting the amount of graphite oxide(GO),the complex dielectric constant of the obtained hybrids can be controlled,and the heterointerface can be cleverly *** minimum reflection loss(RLmin)of the typical products can be up to−73.86 dB at the thickness is only 1.35 mm,and the maximum effective absorption bandwidth(EAB)can reach 5.1 *** work demonstrates that the unique structure and tunable components can fully improve the potential of electromagnetic absorption performance,which provides basic guidance for the heterogeneous interface engineering of efficient electromagnetic functional materials.

关键词： Electromagnetic wave absorption Dielectric regulation Self-assemble Hierarchical structure Composites

Approximation for Ruin Probability in the Sparre Andersen Model with Interest

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Acta Mathematicae Applicatae Sinica 2006年第2期22卷 333-344页

作者： ji-yang tan Xiang-qun Yang Department of Mathematics Hunan Normal University Changsha 410081 China

We consider the Sparre Andersen model modified by the inclusion of interest on the surplus. Approximation for the ultimate ruin probability is derived by rounding. And upper bound and lower bound are also derived by rounding-down and rounding-up respectively. According to the upper bound and lower bound, we can easily obtain the error estimation of the approximation. Applications of the results to the compound Poisson model are given.

关键词： Sparre Andersen model compound Poisson model force of interest ruin probability

A novel bearing-assisted TDOA-GROA approach for passive source localization

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International Journal of Intelligent Computing and Cybernetics 2018年第1期11卷 2-19页

作者： ji-An Luo Zhi-Wen tan Dong-Liang Peng Key Lab for IOT and Information Fusion Technology of Zhejiang Hangzhou Dianzi UniversityHangzhouChina

Purpose–The passive source localization(PSL)problem using angles of arrival(AOA),time differences of arrival(TDOA)or gain ratios of arrival(GROA)is generally nonlinear and *** this research,the purpose of this paper is to design an accurate hybrid source localization approach to solve the PSL *** inspiration is drawn from the fact that the bearings,TDOAs and GROAs are complementary in terms of their geometry ***/methodology/approach–The maximum-likelihood(ML)method is reexamined by using hybrid *** assisted by the bearings,a new hybrid weighted least-squares(WLS)method is then proposed by jointly utilizing the bearing,TDOA and GROA ***–Theoretical performance analysis illustrates that the mean-square error of the ML or WLS method can attain the Cramér-Rao lower bound for Gaussian noiseover small error ***,the WLS method has much lower computational complexity than the ML *** with the AOA-only,TDOA-only,AOA-TDOA,TDOA-GROA methods,the localization accuracy can be greatly improved by combining the AOAs,TDOAs and GROAs,especially for some specific ***/value–A novel bearing-assisted TDOA-GROA method is proposed for source localization,and a new hybrid WLS estimator is presented inspired from the fact that the bearings,TDOAs and GROAs are complementary in terms of their geometry properties.

关键词： Bearing Gain ratio of arrival Hybrid measurements Passive source localization Time difference of arrival

Using geoaccumulation index to study source profiles of soil dust in China

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Journal of Environmental Sciences 2008年第5期20卷 571-578页

作者： ji Yaqin FENG Yinchang WU jianhui ZHU tan BAI Zhipeng DUAN Chiqing State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and Engineering Nankai University Tianjin 300071 China.

Source apportionment studies of TSP （atmospheric particulate matter with aerodynamic diameters ≤ 100 μm） and PM10 （atmospheric particulate matter with aerodynamic diameters ≤ 10 μm） have revealed that soil dust is an important source of these particulates in China. In this study, the contamination of soil dust was assessed through the use of a geoaccumulation index （Igeo）. The mass concentration profiles of 17 elements （Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Ba, and Pb） were established for urban soil dusts. Geochemical compositions of soils from 15 cities were used to represent background urban soil compositions. The results of this study indicated that a number of cities are severely polluted by particulates containing Ca, Cr, Ni, and Cu in both size fractions （TSP and PM10）. Contamination with Zn, Pb, Co, and Br was moderate to severe （Igeo 〉 2）. The Al and Fe concentrations were not high enough for them to be considered contaminants.

关键词： geoaccumulation index soil dust source apportionment TSP PM10

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袁大滩煤矿主斜井带式输送机提能改造设计

煤矿机械 2025年第1期46卷 143-146页

作者：姬红刚中煤科工集团北京华宇工程有限公司西安分公司西安710075

以袁大滩煤矿主斜井带式输送机为例,介绍了主斜井带式输送机提能改造的设计特点:采用低噪声节能托辊和低滚阻节能型输送带来降低运行阻力,采用工期最短的改造方案来减少矿井停产造成的经济损失。改造的思路和方案,可供相关煤矿和设计人... 详细信息

以袁大滩煤矿主斜井带式输送机为例,介绍了主斜井带式输送机提能改造的设计特点:采用低噪声节能托辊和低滚阻节能型输送带来降低运行阻力,采用工期最短的改造方案来减少矿井停产造成的经济损失。改造的思路和方案,可供相关煤矿和设计人员参考借鉴。

关键词：煤矿主斜井带式输送机提能改造节能

Synthesis and Crystal Structure of 4-Salicylimine-3, 5-bis(2-hydroxyphenyl)-1, 2, 4-triazole ji Bao-Minga

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Chinese Journal of Structural Chemistry 2002年第3期21卷 252-255页

作者： ji Bao-Ming DU Chen-Xia ZHU Yu WANG Yang Department of Chemistry Luoyang Teacher's College Luoyang 471022 Department of Chemistry Zhengzhou University Zhengzhou 450052 School of Pharmacy Fudan University 上海 200032

The title compound, 4-salicylimine-3, 5-bis(2-hydroxyphenyl)-1, 2, 4-triazole, was obtained by the condensation reaction of 4-amino-3, 5-bis(2-hydroxyphenyl)-1, 2, 4-triazole with salicylaldehyde in methanol. The crystal structure (C21H16N4O3, Mr = 372.38) belongs to monoclinic system, space group P21/n with a = 10.507(2), b = 16.878(3), c = 11.199(2) ? = 110.86(3), V = 1855.9(6) ?, Z = 4, Dc = 1.333 g/cm3, F(000) = 776, (MoK? = 0.092 mm-1, R = 0.0552 and wR = 0.1095 for 1920 reflections ( I > 2.0(I) ). The analytical results of crystal structure show that there are two different non-covalent interactions in the compound. One is hydrogen bond, and the other p-p stacking interaction. These two types of non-covalent interactions play an important role in the packing of crystal.

关键词： triazole hydrogen bond crystal structure stacking interaction

Experimental research on charging characteristics of a pressure-controlled VRLA battery in high-temperature environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 418-422页

作者： Hua ZHU jin-jun tan Zhang-lu XU ji-sen XU Institute of Thermal Science and Power Systems Zhejiang University Hangzhou 310027 China

Valve-regulated-lead-acid (VRLA) battery charging performed in high-temperature environments is extremely risky under overcharge conditions, and may lead to a subsequent thermal runaway. A new pressure-controlled charging method was adopted and the charging characteristics of the pressure-controlled VRLA battery in high-temperature environments were ex-perimentally studied. The concept was tested in a large temperature gradient to obtain more details about the effects of users' accustomed charging and discharging modes on battery capacity. The premature capacity loss (PCL) phenomenon under high temperature exposure was analyzed. The results showed that the capacity loss could be recovered by charging using a large current.

关键词： Valve-regulated-lead-acid (VRLA) battery Pressure-controlled charging method High-temperature environments Charging and discharging characteristics

An efficient and convenient method for preparation of disulfides from thiols using air as oxidant catalyzed by Co-Salophen

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Chinese Chemical Letters 2011年第12期22卷 1403-1406页

作者： Pin ji Chai Yong Shu Li Cheng Xia tan College of Chemical Engineering and Materials Sciences Zhejiang University of TechnologyHangzhou 310014China College of Pharmaceutical Sciences Zhejiang University of TechnologyHangzhou 310014China

Disulfides have been synthesized by oxidation of thiols using air as oxidant catalyzed by Co-Salophen with high yields,mild and neutral conditions,and easy procedures of the *** products were confirmed by ~1H NMR and IR.

关键词： Disulfides Air Co-Salophen Oxidant Catalyst

Mn-Based Two Dimensional Metal-Organic Framework Material from Benzimidazole-5,6-dicarboxylic Acid

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Chinese Journal of Chemistry 2016年第2期34卷 233-238页

作者： Erpan Zhang Lili Zhang Zhe tan Zhenguo ji Qiaowei Li College of Materials and Environmental Engineering Hangzhou Dianzi University Hangzhou Zhejiang 310018 China Department of Chemistry Fudan University Shanghai 200433 China

A new two-dimensional metal-organic framework （MOF） structure has been synthesized by mild solvothermal reaction of MnC12o4H20 with 1H-benzimidazole-5,6-dicarboxylic acid （H3bidc） at 85℃. The structure has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction （PXRD）, infrared spectroscopy （FT-IR）, and thermogravimetric analysis （TGA）. Single-crystal X-ray diffraction analysis revealed that this MOF is a five-coordinated Mn（II） compound exhibiting a layered 2D network, in which the hydrogen-bonding interactions between uncoordinated carboxylic oxygen atoms and N--H groups in the imidazole rings play a key role in the fi- nal 3D supramolecular architecture. This MOF shows high thermal stability up to 400℃. Furthermore, XRD pattern of the MOF structure was retained for up to 20 d after soaked in water, and only 2.8 wt% of the MOF was decomposed within the first 48 h in water.

关键词： metal-organic framework manganese benzimidazole-5,6-dicarboxylate water stability