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Chinese Journal of Polymer Science 2020年第11期38卷 1258-1266,I0009页

作者： xi-Ting Lei li-fen Tong Ming-Zhen xu Yong You xiao-Bo liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Low dielectric in terlayer films have become an important element to ensure the development of the microelectr onics industry.A kind of flexible interlayer dielectrics,polyarylene ether nitrile/bisphenol A cyanate ester(PEN/BADCy)film,with good thermal stability and low frequency dependence,has been developed by solution casting ***,materials were designed to incorporate bisphenol A cyanate ester as a part of blend,contributing to the frequency stability and structural *** morphological study combined with electron microscopy revealed the uniform and flexible microstructure information with controllable morphology through self-polymerization of cyanate esters with different prepolymerization time and curing *** dielectric films could present high thermal stability with Tg>180℃.Significant improvement in the dielectric properties was achieved for the dielectric constant and loss was much stabler than neat PEN over the frequency range from 100 Hz to 5 *** the prepolymerization time was 3h and final curing temperature reached 230℃,the dielectric constant and dielectric loss of the films were 3.36 and 0.013 at 100 kHz,*** dimensional stability(CTE=53.67×10^-6 K^-1)was confirmed and con sidered beneficial to use as an in terlayer dielectrics.

关键词： Polyarylene ether nitrile Bisphenol A cyanate ester Interlayer dielectrics Tunable microstructures

Fibrous TiO_2 prepared by chemical vapor deposition using activated carbon fibers as template via adsorption,hydrolysis and calcinations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 981-987页

作者： Hui-na YANG li-fen liU feng-lin YANG Jimmy C. YU School of Chemical Engineering Dalian University of Technology Dalian 116023 China School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116023 China Department of Chemistry the Chinese University of Hong Kong Hong Kong China

TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by N2 to an APCVD （chemical vapor deposition under atmospheric pressure） reactor at ≤200 ℃. Activated carbon fibers （ACFs） were used as templates for deposition and later removed by calcinations. The obtained catalysts were characterized by scanning electron micros- copy （SEM）, transmission electron microscopy （TEM）, Brunauer, Emmett and Teller （BET） and x-ray diffraction （xRD） analysis The pores within TiO2 fibers included micro-range and meso-range, e.g., 7 nm, and the specific surface areas for TiO2 fibers were 141 m^2/g and 148 m^2/g for samples deposited at 100 ℃ and 200℃ （using ACFI700 as template）, respectively. The deposition temperature significantly influenced TiO2 morphology. The special advantages of this technique for preparing porous nano-material include no consumption of organic solvent in the process and easy control of deposition conditions and speeds.

关键词： Chemical vapor deposition (CVD) Porous material Activated carbon fiber (ACF)

Effects of rainfall intensity and topography on rill development and rill characteristics on loessial hillslopes in China

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Journal of Mountain Science 2019年第10期16卷 2299-2307页

作者： SHEN Hai-ou ZHENG fen-li WANG Lei WEN Lei-lei College of Resources and Environment Jilin Agricultural UniversityChangchun130118China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling712100China Songliao Water Resources Commission Ministry of Water ResourcesChangchun130021China

Rill development is a major soil erosion process that causes severe soil *** study examined the effects of representative rainfall intensities(50 and 75 mm h-1),slope gradients(10°and 150),and slope lengths(7.5 and 10.0 m)on rill development and rill characteristics on loessial hillslopes in *** soil was collected from the cropland of Ansai Town,Yan’an City,Shaanxi *** soil with 28.3%sand,58.1%silt,and13.6%clay was packed into a soil pan to conduct rainfall simulations in *** results showed that the time of the knickpoint occurrence(5-16 min),the rill headcut extension(9-33 min),and the mean headward erosion rate(1.7-5.o cm min-1)were better representative indicators for reflecting the changes in the rill development than other indicators used in this *** a quick evaluation of the rill erosion severity,the rill coverage ratio(1%-12%,generallyincreasing with an increase in the rainfall intensity)was better than the other indicators for treatments with different rainfall intensities,and the rill width-depth ratio(1.56-2.27,generally decreasing with an increase in the slope gradient)was better than the other indicators for treatments with different slope ***,the rill inclination angle(8.2°-19.1°,significantly increasing with an increase in the slope length)and rill density(0.19-1.34 m·m-2,generally increasing with an increase in the slope length)were more suitable for evaluating the rill erosion severity on hillslopes with different slope ***,the representative indicators could reflect the differences in the rill development and rill characteristics under different rainfall and topographic *** study greatly improved the evaluation of rill erosion severity and the prediction of the development of rills for loessial hillslopes.

关键词： Headward erosion rate Rainfall simulation Slope gradient Slope length

Diagnostic value of orbicularis oculi muscle electromyography in functional epiphora

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World Journal of Clinical Cases 2020年第14期8卷 3000-3005页

作者： Hui Lu Pei-Dong liu xue Yao Zuo-fen Wang li-fen Gao Shao-Peng Wang Department of Ophthalmology Zibo Central HospitalZibo 255000Shandong ProvinceChina Department of Electromyography Zibo Central HospitalZibo 255000Shandong ProvinceChina

BACKGROUND Functional epiphora is a clinical condition which is not due to an anatomic *** studies agree that it involves the action of the orbicularis oculi muscle,particularly its deeper segment(Horner’s muscle),but the exact mechanism is not *** To evaluate the orbicularis oculi muscle in functional epiphora patients using electromyography(EMG).METHODS A total of 8 Chinese patients(16 eyes)with functional epiphora were enrolled in this study,and ten volunteers(10 eyes)were included as normal *** epiphora patients(five eyes)with facial palsy served as positive *** EMG was performed in the deeper segment of orbicularis oculi *** average duration of each EMG waveform was *** The average duration of EMG waveforms in the normal control group,the functional epiphora group,and the facial palsy group were 6.39±0.73 ms,9.39±1.32 ms and 11.2±1.42 ms,*** duration of EMG waveforms was significantly longer in the functional epiphora group than in the normal control group(Pli muscle damage in epiphora patients,which may be the cause of functional *** etiology of neurogenic damage in the orbicularis oculi muscle requires further investigation.

关键词： Functional epiphora Electromyography Orbicularis oculi muscle Neurological damage Etiology Treatment

CdTe QDs@SiO_(2) composite material for efficient photocatalytic degradation of tetracycline composites

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Green Chemical Engineering 2024年第4期5卷 533-542页

作者： Taihang Zhou fen Qiao Sen Qian Shoaib Muhammad Haitao li Yanzhen liu School of Energy&Power Engineering Jiangsu UniversityZhenjiang212013China Institute for Energy Research Jiangsu UniversityZhenjiang212013China

In the contemporary context,tetracycline is widely utilized as a prevalent antibiotic in various facets of ***,the excessive use of antibiotics has caused visible environmental ***,the scientific community has increasingly focused on developing catalysts that exhibit exceptional efficacy in the proficient degradation of *** this study,a novel nanomaterial was developed to encapsulate Cd Te quantum dots(QDs)with a SiO_(2)*** distinct synthesis approach generated a composite material that showed heterogeneity and considerably increased the contact area with ***,the transfer of photoelectron to the SiO_(2)spheres was significantly improved,leading to a more efficient separation during the catalytic *** study investigated how different factors,such as the loading of the catalyst,the initial concentration of tetracycline,p H levels,and the wight ratio of Cd Te QDs(SiO_(2)+Cd Te QDs)affected the effectiveness of photocatalytic tetracycline *** findings indicated that the optimal degradation efficiency was observed at a catalyst concentration of 0.25 g/L and a solution p H of 9,leading to an impressive degradation rate of 96%within a mere 2 h timeframe.

关键词： Photocatalysis Silica-based catalyst Photocatalytic degradation Photocatalytic mechanism

Choline dehydrogenase interacts with SQSTM1 to activate mitophagy and promote coelomocyte survival in Apostichopus japonicus following Vibrio splendidus infection

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Zoological Research 2023年第5期44卷 905-918页

作者： lian-lian Sun Ying-fen Dai Mei-xiang You Cheng-Hua li State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Ningbo UniversityNingboZhejiang 315211China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266071China

Previous studies have shown that Vibrio splendidus infection causes mitochondrial damage in Apostichopus japonicus coelomocytes,leading to the production of excessive reactive oxygen species(ROS)and irreversible apoptotic cell *** evidence suggests that mitochondrial autophagy(mitophagy)is the most effective method for eliminating damaged mitochondria and ROS,with choline dehydrogenase(CHDH)identified as a novel mitophagy receptor that can recognize non-ubiquitin damage signals and microtubule-associated protein 1 light chain 3(LC3)in ***,the functional role of CHDH in invertebrates is largely *** this study,we observed a significant increase in the mRNA and protein expression levels of *** CHDH(AjCHDH)in response to *** infection and lipopolysaccharide(LPS)challenge,consistent with changes in mitophagy under the same ***,AjCHDH was localized to the mitochondria rather than the cytosol following *** ***,AjCHDH knockdown using si RNA transfection significantly reduced mitophagy levels,as observed through transmission electron microscopy and confocal *** investigation into the molecular mechanisms underlying CHDH-regulated mitophagy showed that AjCHDH lacked an LC3-interacting region(liR)for direct binding to LC3 but possessed a FB1 structural domain that binds to *** interaction between AjCHDH and SQSTM1 was further confirmed by immunoprecipitation ***,laser confocal microscopy indicated that SQSTM1 and LC3 were recruited by AjCHDH in coelomocytes and HEK293T *** contrast,AjCHDH interference hindered SQSTM1 and LC3 recruitment to the mitochondria,a critical step in damaged mitochondrial ***,AjCHDH interference led to a significant increase in both mitochondrial and intracellular ROS,followed by increased apoptosis and decreased coelomocyte ***,these findings indicate that AjCHDH-mediated mitophagy plays a

关键词： Choline dehydrogenase Mitophagy SQSTM1 Microtubule-associated protein 1 light chain 3 Apostichopus japonicus

Synthesis and Crystal Structure of [Cu(bbtz)(HCOO)_2(H_2O)_2]_n

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Chinese Journal of Structural Chemistry 2006年第7期25卷 793-796页

作者： PENG Yan-fen liLT Tian-Bao YANG xiao-Hong li Bao-Long Department of Chemistry Chizhou Teachers College Chizhou 247100 China College of Chemistry and Chemical Engineering Key Lab of Organic Synthesis of Jiangsu Province Suzhou University Suzhou 215123 China

The title compound [Cu（bbtz）（HCOO）2（H2O）2], （bbtz = 1,4-bis（1,2,4-triazol-1- ylmethyl）-benzene） was synthesized by the reaction of Cu（HCOO）2 and bbtz in methanol/H2O solution and its structure was determined by single-crystal x-ray diffraction. Crystal data： C14H18CuN6O6, monoclinic, space group P2 1/c, a = 9.651（2）, b = 10.380（2）, c = 9.368（2） A, β = 112.905（5）°, V = 864.5（3） A^3, Mr = 429.88, Z = 2, Dc = 1.651 g/cm^3, F（000） = 442, μ = 1.311 mm^-1, the final R = 0.0305 and wR = 0.0856 for 1891 observed reflections with I 〉 2σ（I）. x-ray crystal-structure analysis suggests the central copper atom of the title compound is six-coordinated in a distorted octahedral geometry by two nitrogen atoms from two bbtz ligands as well as four oxygen atoms from two H2O and two HCOO^-. The copper atoms are linked by bridging ligand bbtz to form a one-dimensional chain. There are intra- and interchain hydrogen bonding interactions between hydrogen atoms of coordinated water and uncoordinated oxygen atom of HCOO^-.

关键词： synthesis crystal structure cooper complex triazole ligand

Application of EDTMPS as a novel calcite depressant in scheelite flotation

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International Journal of Mining Science and Technology 2023年第5期33卷 639-647页

作者： fen Jiao Wei li xu Wang Congren Yang Zhengquan Zhang liwen Fu Wenqing Qin School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mechanism was revealed by contact angle measurement, FTIR analysis, Zeta potential test and xPS analysis. The flotation experiment results showed that scheelite and calcite could be efficiently separated under the following conditions: pulp p H=9.5, Na OL concentration of 1.5×10^(-4)mol/L, EDTMPS concentration of 3.0×10^(-5)mol/L, a scheelite concentrate with WO3grade of 65.49%, recovery of 83.29%and separation efficiency of 65.29% could be obtained from the artificially mixed minerals. The analysis results of mineral surface properties demonstrated that EDTMPS was strongly adsorbed onto the calcite surface through the reaction between the phosphonate group and the calcium ions, which hindered Na OL adsorption and increased the hydrophilicity of calcite. However, EDTMPS had weak adsorption strength on the scheelite surface, which didn’t affect further adsorption of Na OL, hence, the scheelite remained hydrophobic. Consequently, the selective adsorption of EDTMPS on the two minerals’ surfaces increased a difference in wettability and thus enabling them to be separated by flotation. Finally, the mechanism model of this flotation separation process was established.

关键词： Ethylenediamine tetramethylene phosphonic sodium Scheelite Calcite Flotation Selective depression

Effect of Ti/Nb/Ta addition on the γ/γ'coherent microstructure in low-density and high-strength Co-Al-W-Mo-based superalloys

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材料科学技术（英文版） 2024年第19期186卷 174-187页

作者： Jinlin li Jiaqi Zhang Zhen li Qing Wang Chuang Dong fen xu lixian Sun Peter K.liaw School of Materials Science and Engineering Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)Dalian University of TechnologyDalian 116024China School of Aeronautics and Astronautics Shenyang Aerospace UniversityShenyang 110136China School of Mechanical Engineering Dalian University of TechnologyDalian 116024China Guangxi Collaborative Innovation Center of Structure and Property for New Energy Materials Guangxi Key Laboratory of Information MaterialsGuilin University of Electronic TechnologyGuilin 541004China Department of Materials Science and Engineering The University of TennesseeKnoxville37996TNUSA

Coherent precipitation of cuboidal γ'-Co3(Al,W)nanoparticles in face-centered-cubic(FCC)-γ matrix is of great significance for improving high-temperature mechanical properties of Co-based *** present work developed a series of low-density Co-based superalloys in light of the cluster composi-tion formula of[Al1-(Co,Ni)12]((Al0.5(Ti/Nb/Ta)0.5W0.5)(Mo0.5Cr0.5Co0.5)),where the addition of Ti,Nb,and Ta is mixed with an equimolar *** is found that these designed alloys with different combinations of Ti/Nb/Ta,Ti/Nb,and Ti/Ta possess the coherent microstructure of cuboidal γ'nanoprecipitates in the FCC-y *** microstructural evolution of coherent γ/γ'during aging at 1173 K shows that these superalloys exhibit higher thermal stability at high *** after aging for 1000 h,there do not exist any other precipitated phases on grain boundaries,except the coarse γ'***,the coarsening rate constants of cuboidal γ'nanoprecipitates in these alloys are very low(K=5.76-6.03 nm3/s),which is mainly ascribed to a moderate lattice misfit(ε=0.28％-0.45％)between γ and γ'.The stable γ/γ'microstructure renders the alloys with prominent mechanical properties,as evidenced by the high yield strength of σYS=438-445 MPa at 1143 K.A large amount of stacking faults appear after compressive deformation and Lomer-Contrell dislocation locks are also formed due to the reaction of partial dislocations of stacking ***,the microhardness(285-320 HV)in each alloy keeps almost constant with the aging ***,these superalloys have a relatively lower density(8.67-8.89 g/cm3),among which the alloy containing Ti0.25Ta0.25 also exhibits a much higher γ'solvus temper-ature(1361±2 K)than those of the existing Co-Al-W-based superalloys.

关键词： Co-based superalloys Coherent microstructure Lattice misfit Particle coarsening Mechanical properties

Large magnetic refrigerant capacity of HoFe_(1-x)Co_(x)Al(x=0,0.3)compounds

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Rare Metals 2021年第10期40卷 2868-2872页

作者： Zhi-Yi xu Zhi-Gao Zhang Rong-li Gao Wen-Jie Gong Rui-fen Hou An-li lin National Institute of Metrology(NIM) Beijing 100029China School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China

Magnetic and magnetocaloric properties of HoFe_(1-x)Co_(x)Al(x = 0, 0.3) were investigated. Both HoFeAl and HoFe_(0.7)Co_(0.3) Al undergo a second-order ferromagnetic(FIM) to paramagnetic(PM) transition at Curie temperatures(TC) of 87 and 82 K, respectively. The magnetocaloric effect is improved by the introduction of Co in HoFeAl compound. For a field change from 0 to 5 T,the maximum values of magnetic entropy change(﹣△SM)are 7.0 J·kg^(-1)·K^(-1) for HoFeAl and 8.6 J·kg^(-1)·K^(-1) for HoFe_(0.7)Co_(0.3) Al. In addition, the refrigerant capacity(RC)is enhanced largely from 416.2 J·kg^(-1) for HoFeAl to561.9 J·kg^(-1) for HoFe_(0.7)Co_(0.3) Al. This large RC is attributed to the large ﹣?SM and the wide temperature span of ?SM peak in HoFe_(0.7)Co_(0.3) Al compound. The physical mechanism of improvement in magnetocaloric effect by Co substitution in HoFeAl was also discussed in detail.

关键词： RTx compound Intermetallic compound Magnetocaloric effect Refrigerant capacity