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Chemical Research in Chinese Universities 2010年第4期26卷 662-666页

作者： ZANG jun-ting qi Xin li Shu-qiang li Dong-song GONG Yu-bao YANG Chen XU Feng liU Jian-guo Department of Bone and Joint Surgery First Hospital of Jilin University Changchun 130021 P R. China

A novel scaffold containing collagen-I/polylactic acid（PLA）/nanohydroxyapatite（nHA） was prepared via co-electrospinning method. Different target substrates were used to improve the collection efficiency of this scaffold. The properties of the novel scaffold were compared with those of conventionally prepared ones. Compared to con- ventional method, the modified method was more efficient in producing the scaffold. Moreover, the porosity, thickness, and morphology of the novel scaffold were better than those of scaffolds prepared by conventional methods. The properties of collagen-I, collagen-I/PLA and collagen-I/PLA/nHA scaffolds were also compared. Diameters of the electrospun fibers ranged from 180 to 405 nm, and roughness was present on the surface of the fibers due to the deposition of crystals of nHA along the long axis of the fibers. The fibers of the collagen-I/PLA/nHA scaffold and the fibers of natural bone tissue had similar structure.

关键词： Electrospinning Collagen-I PLA Nanohydroxyapatite

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang Rui qiu An-Kang Hu Ye-qi liu Zhen Wu Hui Zhang jun-li li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Realizing the excellent oxidation resistance of an environmental barrier coating through aluminum surface modification

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Journal of Advanced Ceramics 2024年第7期13卷 976-986页

作者： lin Dong Wen-qi Yang lin Chen Guan-jun Yang Chang-Jiu li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company limited in China Aerospace Science and Technology Corporation Xi’an 710065China

The lifetime of Si-based environmental barrier coatings(EBCs)is constrained by thermally grown SiO_(2)oxidelayer(SiO_(2)-TGO),which can cause premature cracking and *** address this issue,a new approach for surfacemodification using aluminum is *** oxidation performance was examined in a 50 vol%H_(2)O-50 vol%O_(2)environment at 1350℃for up to 300 *** results indicate that a dense ytterbium aluminum garnet(YbAG)layer wasformed after modification,decreasing the porosity by 80%.Due to the elimination of fast diffusion channels and the lowoxygen permeability of YbAG,aluminum modification significantly reduced the growth rate of SiO_(2)-TGO by nearly twoorders of ***,its thickness decreased by more than 70%after 300 h of exposure.A diffusioncontrolled oxidation mechanism indicates that the modified dense surface is equivalent to an initial SiO_(2)layer with a specificthickness,causing a shift in the oxidation time and increasing the oxidation *** research provides valuableinsights for designing Si-based EBC with improved lifetimes.

关键词： environmental barrier coating(EBC) oxidation modification diffusion cracking

Assessing target optical camouflage effects using brain functional networks:A feasibility study

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Defence Technology（防务技术） 2024年第4期34卷 69-77页

作者： Zhou Yu li Xue Weidong Xu jun liu qi Jia Jianghua Hu Jidong Wu National Key Laboratory of lightning Protection and Electromagnetic Camouflage Army Engineering University Nanjing 210007JiangsuChina Unit 31608 of PLA Xiamen 361000FujianChina School of Biological Sciences&Medical Engineering Southeast UniversityNanjing 210096JiangsuChina

Brain functional networks model the brain's ability to exchange information across different regions,aiding in the understanding of the cognitive process of human visual attention during target searching,thereby contributing to the advancement of camouflage *** this study,images with various camouflage effects were presented to observers to generate electroencephalography(EEG)signals,which were then used to construct a brain functional *** topological parameters of the network were subsequently extracted and input into a machine learning model for *** results indicate that most of the classifiers achieved accuracy rates exceeding 70%.Specifically,the Logistic algorithm achieved an accuracy of 81.67%.Therefore,it is possible to predict target camouflage effectiveness with high accuracy without the need to calculate discovery *** proposed method fully considers the aspects of human visual and cognitive processes,overcomes the subjectivity of human interpretation,and achieves stable and reliable accuracy.

关键词： Camouflage effect evaluation Electroencephalography(EEG) Brain functional networks Machine learning

Effect of short neuropeptide F signaling on larval feeding in Mythimna separata

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Insect Science 2024年第2期31卷 417-434页

作者： Mei-Mei li qi Yang li-Hui Chen Yan-Ying li jun-Xiang Wu Xiang-li Xu State Key Laboratory of Crop Stress Biology in Arid Areas College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi ProvinceChinaand School of Agricultural Sciences Jiangxi Agricultural UniversityNanchangChina

Mythimna separata is a notorious phytophagous pest which poses serious threats to cereal crops owing to the gluttony of the *** short neuropeptide F(sNPF)and its receptor sNPFR are involved in a diversity of physiological functions,especially in functions related to feeding in insects,it is a molecular target for pest ***,an sNPF and 2 sNPFRs were identified and cloned from *** analysis revealed that the sNPF and its receptors had a highly conserved RLRFamide C-terminus and 7 transmembrane domains,*** sNPF and its receptor genes were distributed across larval periods and tissues,but 2 receptors had distinct expression *** starvation-induced assay elucidated that sNPF and sNPFR expression levels were downregulated under food deprivation and recovered with subsequent *** interference knockdown of sNPF,sNPFR1,and sNPFR2 by injection of double-stranded RNA into larvae not only suppressed food consumption and increased body size and weight,but also led to decrease of glycogen and total lipid contents,and increase of trehalose compared with double-stranded green fluorescent protein ***,molecular docking was performed on the interaction mode between sNPFR protein and its ligand sNPF based on the 3-dimensional models constructed by AlphaFold;the results indicated that both receptors were presumably activated by the mature peptide *** results revealed that sNPF signaling played a considerably vital role in the feeding regulation of *** and represents a potential control target for this pest.

关键词： feeding regulation Mythimna separata pest control target RNA interference short neuropeptide F sNPF receptors

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan qi Xin Zhang jun li Dong-liang Zhao Shi-hai Guo Yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

Durable dual-state duplex Si-HfO_(2)with excellent oxidation and cracking resistance

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Journal of Advanced Ceramics 2024年第3期13卷 388-401页

作者： lin Chen Jing-Chuan Luo Wen-qi Yang Chang-Jiu li Guan-jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company limited in CASC Xi’an 710065China

The lifetime of Si bond coatings in environmental barrier coatings is constrained by phase-transition-induced cracking of the SiO_(2)*** this study,Si-HfO_(2)dual-state duplex composite materials are proposed to address this issue by partially forming HfSiO_(4)and minimizing the SiO_(2)*** as-prepared composite exhibited a structure comprising discrete HfO_(2)“bricks”embedded in a continuous Si“mortar”,while the oxidized state transformed into discrete HfSiO_(4)“bricks”within continuous thin SiO_(2)“mortars”.The results indicate that continuous thin SiO_(2)contributes to reducing the oxidation rate to a level comparable to that of pure Si,and discrete HfSiO_(4)particles aid in relieving phase transition-induced stress and inhibiting crack propagation,thereby enhancing oxidation and cracking resistance ***,the composite with 20 mol%HfO_(2)and a mean particle size of~500 nm at 1370℃exhibited a service lifetime 10 times greater than that of pure *** research provides valuable insights for designing Si-based bond coatings with improved service lifetime.

关键词： oxidation environmental barrier coatings(EBCs) phase transition cracking bond coatings

Achieving high carrier mobility and low lattice thermal conductivity in GeTe-based alloys by cationic/anionic co-doping

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Rare Metals 2024年第6期43卷 2784-2795页

作者： Xiao-qiang Wang Xiao-Quan Hu jun-Yan lin Chu-Bin li Xiao-Tong Yu qi-Yong Chen li-li Xi qi-Shuo Yang Han li Ji-Ye Zhang Shuan-Kui li Kai Guo School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Research Center for Advanced Information Materials(CAIM) Huangpu Research&Graduate School of Guangzhou UniversitySino-Singapore Guangzhou Knowledge CityGuangzhou510555China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China School of Mechanical and Mining Engineering University of QueenslandBrisbaneQLD 4072Australia Key Laboratory of Si-Based Information Materials&Devices and Integrated Circuits Design Department of Education of Guangdong ProvinceGuangzhou 510006China

TheⅣ-Ⅵcompound GeTe is considered as a promising alternative to the toxic PbTe for high-efficiency mid-temperature thermoelectric ***,pristine GeTe suffers from a high concentration of Ge vacancies,resulting in an excessively high hole concentration(>1×10^(21)cm^(-3)),which greatly limits its thermoelectric *** address this issue,CuBiTe_(2)alloying is introduced to increase the formation energy of Ge vacancies in GeTe,thereby inhibiting the high carrier *** carrier scattering caused by the electronegativity difference between different elements is suppressed due to the similar electronegativity of Cu and Ge atoms.A relatively high hole mobility is obtained,which ultimately leads to a high power ***,by introducing Se as an alloying element at the anionic site in GeTe,dense point defects with mass/strainfield fluctuations are *** contributes to the strengthening of phonon scattering,thereby reducing the lattice thermal conductivity from 1.44 W·m^(-1)·K^(-1)for pristine GeTe to 0.28 W·m^(-1)·K^(-1)for Ge_(0.95)Cu_(0.05)Bi_(0.05)Te_(0.9)Se_(0.15)compound at 623 K.

关键词： GeTe Carrier mobility CuBiTe_(2)alloying Lattice thermal conductivity Thermoelectric properties

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia qi-lin Ma Yu Hou Ba li He-song Zhang qing-you liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

Regulating metal-acid double site balance on mesoporous SiO2-Al2O3 composite oxide for supercritical n-decane cracking

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Petroleum Science 2024年第4期21卷 2881-2891页

作者： liu-ling Chen jun Zhang Chun-Guang li li-Qun Fei Bo Wang Chen-qi Zhang Yi Jiao Jian-li Wang Institute of New Energy and Low-Carbon Technology Sichuan University Engineering Research Center of Combustion and Cooling for Aerospace Power Ministry of Education School of Chemical Engineering Sichuan University State Key Laboratory of Industrial Vent Gas Reuse Southwest Institute of Chemical Co. Ltd Science and Technology on Scramjet Laboratory Beijing Power Machinery Research Institute

The balance between metal and acid sites directly affects the preparation of high-performance cracking catalysts with high heat sink and low ***,how to control acid-metal sites balance and its relationship with cracking performance are reported *** this work,a series of Pt/Al2O3-SiO2dual sites catalysts with different metal to acid active sites ratio(CM/CSA) were constructed by ethanolassisted impregnation method and the impact on n-decane cracking under supercritical conditions was systematically and deeply *** results showed that the conversion and carbon deposition increased gradually with varied CM/CSAand reached the balance at CM/CSAof *** proper ratio CM/CSA（0.13） can balance the deep dehydrogenation coking over metal active sites and high heat sink of cracking over acid active sites,the chemical heat sink reaches amazing 1.75 MJ/kg and carbon deposition is only22.03 mg/cm2at 750℃.Meanwhile,the few metal sites at low CM/CSAand the few strong acid sites at high CM/CSAare the main factors limiting the cracking *** CM/CSAlimit the activation of C-H bond and deep dehydrogenation of coking precursor,resulting in relative low cracking activity and carbon deposition,while high CM/CSAlimit the activation of C-C bond and increase the deep *** this contribution,design and construction of metal-acid dual sites can not only provide the technical solution for the preparation of high heat sink and low coking cracking catalyst,but also deepen the understanding of the cracking path of hydrocarbon fuel.

关键词： Metal-acid dual sites balance Catalytic cracking Hydrocarbon fuels Chemical heat sink Carbon deposition