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Influence of(Mg_(1/3)Nb_(2/3))complex substitutions on crystal structures and microwave dielectric properties of li2TiO3 ceramics with extreme low loss

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Journal of Materiomics 2018年第4期4卷 368-382页

作者： Huan-Huan Guo Di Zhou li-Xia pang Jin-Zhan Su Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic and Information EngineeringXi'an Jiaotong UniversityXi'an710049China Micro-optoelectronic Systems Laboratories Xi'an Technological UniversityXi'an710032ShaanxiChina International Research Centre for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'anShaanxi710049China

A systematic investigation of the li2Ti1-x(Mg_(1/3)Nb_(2/3))xO_(3)(0.1≤x≤0.35)solid solutions synthesized by traditional solid-state reaction method is reported in this *** the composition range of 0.1≤x≤0.25,a monoclinic rock salt structured solid solution was *** x increased to 0.3,a phase transition from monoclinic to cubic phase,along with an order-disorder phase transition,was *** x increased from 0.1 to 0.35,the microwave permittivity(εr)and temperature coefficient of resonant frequency(TCF)of the li2Ti1-x(Mg_(1/3)Nb_(2/3))xO_(3)ceramics decreased linearly from 21.0 to 18.6,+27.1 to-19.4 ppm/℃,*** li_(2)Ti_(0.75)(Mg_(1/3)Nb_(2/3))0.25O_(3)ceramic sintered at 1170℃shows high performance of microwave dielectric properties with aεr~19.6,a Qf(Q=quality factor=1/dielectric loss;f=resonant frequency)~109,770 GHz(at 7.7 GHz)and a near zero TCF~t 1.2 ppm/℃.Moreover,the burying sintering process can reduce the volatilization of lithium so that the porosity of li_(2)Ti_(0.75)(Mg_(1/3)Nb_(2/3))0.25O_(3)ceramic was reduced effectively,which made li_(2)Ti_(0.75)(Mg_(1/3)Nb_(2/3))0.25O_(3)ceramic promising for future *** area electron diffraction patterns,high-resolution transmission electron microscopy,Raman and far-infrared spectra were employed to study the relation between crystal structure and microwave dielectric properties in detail.

关键词： Microwave dielectric properties Phase evolution Crystal structure High quality

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Choriocarcinoma with lumbar muscle metastases:A case report

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World Journal of Clinical Cases 2020年第20期8卷 5036-5041页

作者： li pang Xiao-Xin Ma Department of Obstetrics and Gynecology Shengjing Hospital Affiliated to China Medical UniversityShenyang 110004Liaoning ProvinceChina

BACKGROUND Choriocarcinoma is a highly malignant trophoblastic tumor that presents with early symptoms similar to those of an ectopic *** we present a patient with suspected ectopic pregnancy diagnosed by laparoscopic surgery in our *** patient was found to have choriocarcinoma that had metastasized to the lumbar muscle and presented with symptoms similar to those of an ectopic *** SUMMARY The patient was a 34-year-old female who complained of amenorrhea lasting 53 d,7 d of right lower back pain,and 3 d of right lower abdominal *** ultrasonography revealed the absence of a gestational sac in the uterus and a mass in the left *** 6 d of re-examination,ultrasound and computed tomography(CT)examination were performed on the mass located in the left adnexa *** also noted that the patient's serumβ-human chorionic gonadotropin(h CG)level was *** an ectopic pregnancy,we performed a laparoscopy and *** the operation,a left ovarian mixed echogenic mass approximately 2.5 cm×2.0 cm with no villous tissue was *** levels of serum h CG continued to *** CT examination showed lung *** CT and magnetic resonance imaging showed a mixed echogenic mass in the lumbar *** lumbar metastasis of choriocarcinoma,six courses of cisplatin,dactinomycin,and etoposide chemotherapy were given after *** patient's serumβ-h CG level decreased to normal and the mixed echogenic mass in the lumbar muscle decreased in size after the fifth course of *** symptoms subsequently disappeared after *** In summary,lumbar metastasis from choriocarcinoma is extremely *** chemotherapy can successfully treat these metastasized tumors.

关键词： Choriocarcinoma Ectopic pregnancy Lumbar Malignant trophoblastic tumor Metastasis Human chorionic gonadotropin Case report

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An Inexact Modified Newton Method for Viscc and Application in Grasping Force

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 591-606页

作者： Shuang CHEN li-ping pang Dan li Jin-he WANG Information and Engineering College of Dalian University Dalian 116622China School of Mathematical Science Dalian University of TechnologyDalian 116024China School of Engineering Huzhou UniversityHuzhou 313000China

For the variational inequality with symmetric cone constraints problem,we consider using the inexact modified Newton method to efficiently solve *** provides a unified framework for dealing with the variational inequality with nonlinear constraints,variational inequality with the second-order cone constraints,and the variational inequality with semi-definite cone *** show that each stationary point of the unconstrained minimization reformulation based on the Fischer-Burmeister merit function is a solution to the *** is proved that the proposed algorithm is globally convergent under suitable *** computation results show that the feasibility and efficiency of our algorithm.

关键词： variational inequality symmetric cone inexact modified Newton method Fischer-Burmeister function

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Two-step accelerated mineral carbonation and decomposition analysis for the reduction of CO_2 emission in the eco-industrial parks

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Journal of Environmental Sciences 2014年第7期26卷 1411-1422页

作者： Seok Jung li pang Wang Gjergj Dodbiba Toyohisa Fujita Department of Systems Innovation Graduate School of Engineering The University of TokyoBunkyo-Ku Tokyo 113-8656 Japan

Carbon dioxide（CO2） emissions are a leading contributor to the negative effects of global warming. Globally, research has focused on effective means of reducing and mitigating CO2 emissions. In this study, we examined the efficacy of eco-industrial parks（EIPs） and accelerated mineral carbonation techniques in reducing CO2 emissions in South ***, we used Logarithmic Mean Divisia Index（LMDI） analysis to determine the trends in carbon production and mitigation at the existing EIPs. We found that, although CO2 was generated as byproducts and wastes of production at these EIPs, improved energy intensity effects occurred at all EIPs, and we strongly believe that EIPs are a strong alternative to traditional industrial complexes for reducing net carbon emissions. We also examined the optimal conditions for using accelerated mineral carbonation to dispose of hazardous fly ash produced through the incineration of municipal solid wastes at these EIPs. We determined that this technique most efficiently sequestered CO2 when micro-bubbling, low flow rate inlet gas, and ammonia additives were employed.

关键词： CO2 emissionsLMDI analysisAccelerated mineral carbonation EIPs

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Detection of Multi-dimensional Driving Forces of Public Environmental Concern in China:Based on Spatial Heterogeneity Perspectives

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Chinese Geographical Science 2023年第6期33卷 1109-1126页

作者： TONG Yun pang li SUN Minghui HAN Junyi School of Tourism Hainan UniversityHaikou570228China Hainan Province Holistic Tourism Research Base Haikou570228China Academician Station of Hainan Province Haikou570228China

Public environmental concern(PEC)is an important bottom-up force in building an environmentally sustainable *** by attitude theory,this paper innovatively constructed a PEC evaluation index system,while introducing entropy weighted-TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)to realize the assessment of *** spatial data analysis was used to portray the spatio-temporal evolution patterns of PEC in 362 Chinese cities at prefecture-level and above from 2011 to ***,the Geodetector model was performed to identify the multi-dimensional determinants of PEC from the perspective of spatial *** results indicated that:1)PEC in China exhibited a fluctuating upward trend,consistent with the spatial distribution law of‘Heihe-Tengchong line’and‘Bole-Taipei line’;2)the driving effect of each factor varied dynamically,but in general,economic development level,population size,industrial wastewater,and education level were the dominant driving factors explaining the spatial variation of PEC;3)risk detection revealed that four factors,government environmental regulations,PM_(2.5),vegetation coverage,and natural resource endowment,had nonlinear effects on PEC;4)the interactions between factors all demonstrated an enhancement in explaining the spatial differentiation of *** was driven by the comprehensive interaction of four-dimensional factors of economy,society,pollutant emissions,and *** them,population agglomeration accompanied by a high level of regional economy and information technology can explain the increase in PEC to the greatest extent.

关键词： public environmental concern(PEC) spatio-temporal variations driving factors Geodetector Baidu Index spatial heterogeneity

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Thermal Kinetics and Decomposition Mechanism of 1-Amino-1,2,3-triazolium Nitrate

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Chemical Research in Chinese Universities 2014年第1期30卷 130-136页

作者： DU Xujie li Xiaodong YANG Rongjie li Yuchuan pang Siping School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 P. R. China

The thermal decomposition kinetics of 1-amino-l,2,3-triazolium nitrate（ATZ-NO3） was investigated by non-isothermal TG-DTG at various heating rates（2,5,10,15 and 20 ℃/min）.The results show that the thermal decomposition of ATZ-NO3 consists of two stages corresponding to the losing of nitrate anion,substituent group and the splitting of triazole ring *** kinetic triplets of the two stages were described by a three-step ***,the differential Kissinger and intergral Ozawa methods were used to calculate the apparent activation energies（E） and pre-exponential factors（A） of the two decomposition ***,two calculation methods（intergral （S）atava-（S）esták and differential Achar methods） were used to obtain several probable decomposition mechanism ***,three judgment methods（average,double-extrapolation and Popescu methods） were used to confirm the most probable decomposition mechanism *** reaction models of the two stages were randominto-nucleation and random-growth mechanisms with n=3/2 for the first stage and n=1/3,m=3 for the second *** kinetic equations for the two decomposition stages of ATZ-NO3 may be expressed as da/dt=1013.60·e-128970/RT（1-α）[-1n（1-α）]-1/2 and da/dt=1011.41·e-117370/RT（1-α）[-1n（1-α）]-2/*** thermodynamic parameters including Gibbs free energy of activation（△G≠）,entropy of activation（△S≠） and enthalpy of activation（△H≠）,for the thermal decomposition reaction were also derived.

关键词： 1-Amino-1,2,3-triazolium nitrate Thermal decomposition Thermal gravimetric analysis Non-isothermal kinetics Gibbs free energy of activation(△G≠) Kinetic triplets Compensation effect

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The UV-Decomposition on a Class of *** and Optimality Conditions

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Acta Mathematicae Applicatae Sinica 2007年第1期23卷 29-38页

作者： Wei Wang li-Ping pang Zun-Quan Xia School of Mathematics Liaoning Normal University Dalian 116029 China Department of Physics Dalian University of Technologe Dalian 116024 China. Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

In this paper, the uV-theory and P-differential calculus are employed to study second-order expansion of a class of D,C, functions and minimization problems. Under certain conditions, some properties of the u-Lagrangian, the second-order expansion of this class of functions along some trajectories are formulated. Some first and second order optimality conditions for the class of D,C, optimization problems are given.

关键词： Nonlinear programming nonsmooth optimization optimality condition,uv-decomposition,D.C. optimization

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Two new glycosides from the seeds of Cassia obtusifolia

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Chinese Chemical Letters 2009年第9期20卷 1097-1099页

作者： Cun Zhang Gui liu li Yong Qing Xiao li li Zhen pang Institute of Traditional Chinese Materia Madica Chinese Academy of Chinese Medical Sciences Beijing 100700 China

Two new glycosides, nor-rubrofusadn-6-O-β-D-（6＇-O-acetyl）glucopyranoside （1） and 1-desmethylaurantio-obtusin-2-O-β-D- glucopyranoside （2） were isolated from the seeds of Cassia obtusifolia and their structures were established by chemical and spectral evidences. 2009 Yong Qing Xiao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cassia obtusifolia Nor-rubrofusarin-6-O-β-D-(6'-O-acetyl)glucopyranoside 1-Desmethylaurantio-obtusin-2-O-β-D-glucopyranoside

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Synthesis and Photochromism of Novel Spiro（indoline-2,3＆#39;-naphtho [2,1-b] [1,4] oxazine）

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Chemical Research in Chinese Universities 2015年第3期31卷 357-361页

作者： li Hong pang Meili GUO Xinfu MENG Jiben Department of Chemistry Nankai University Tianjin 300071 P.R.China

A series of novel spirooxazine（SPO） derivatives containing nitrogen heterocycles was synthesized and characterized by 1H NMR spectra, Fourier transform infrared（FTIR） spectra, mass spectra（MS） and elemental analy- sis, and their photochromic behaviors were fully investigated in solvents and polymer media. In solvents, they dis- played excellent photochromism properties such as high photochromic response and fast thermal bleaching rate. Es- pecially, compounds 1 and 4 exhibited strong fluorescence intensities in dichloromethane solution. It was additionally found that compound 4 showed high fatigue resistence in poly（methyl methacrylate）（PMMA） film, and the thermal decay curves were fitted with biexponential function in PMMA film.

关键词： Spirooxazine Photochromism Acidichromism Fatigue resistance

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Flow hydrogen absorption of LaFe_(10.9)Co_(0.8)Si_(1.3) compound under constant low hydrogen gas pressure

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Rare Metals 2018年第3期37卷 243-248页

作者： Bin Fu Jun He Jie Han Jie Hu li-Wei pang Tianjin Key Laboratory for Photoelectric Materials & Devices School of Materials Science and EngineeringTianjin University of Technology Division of Functional Material Research Central Iron and Steel Research Institute College of Science Tianjin University of Technology School of Materials Science and Engineering Shijiazhuang Tiedao University

The hydrogen absorption of the LaFe（10.9）-Co（0.8）Si（1.3） compound under constant 1.01 × 10-5 Pa H2 gas in a flow hydrogen atmosphere was studied. The effects of hydrogen absorption on structure, Curie temperature, phase transition and magnetic property were investigated by X-ray diffraction（XRD）, differential scanning calorimeter（DSC） and superconducting quantum interference device,respectively. The hydrides of LaFe（10.9）Co（0.8）Si（1.3） crystallize into NaZn（13）-type structural phase after hydrogen absorption at temperature from 548 to 623 K. Lower hydrogen absorption temperature is of no advantage for pure 1：13 phase formation in a flow H2 atmosphere. The Curie temperature（TC） of LaFe（10.9）Co（0.8）Si（1.3） compound increases by70 K or more after hydrogen absorption. For LaFe（10.9）-Co（0.8）Si（1.3）H（1.8） compound, the maximum magnetic entropy change and the relative cooling power under a magnetic field change of 0-2 T are 6.1 J·kg^-1·K^-1 and 170 J·kg^-1,respectively. Large refrigerant capacity, low hysteresis loss and wide temperature span of magnetic entropy change peak make it a competitive practical candidate for magnetic refrigerant.

关键词： La(FexSi1-x)13 compounds Magnetic refrigerant Hydrogen absorption Magnetic entropy change

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