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基于创新能力培养的航空航天大类本科毕业设计制度研究

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教育教学论坛 2024年第18期 20-23页

作者：严启龙敖文岳晓奎西北工业大学航天学院陕西西安710072

本科毕业设计环节以培养既有实践能力又有创新意识和创新能力人才为根本目标。在系统梳理现有毕业设计方案的基础上,提出了现有模式成效不显著的问题。重点阐述了创新实践基地培养模式、研究生指导本科生的“传帮带”培养模式、基于“... 详细信息

本科毕业设计环节以培养既有实践能力又有创新意识和创新能力人才为根本目标。在系统梳理现有毕业设计方案的基础上,提出了现有模式成效不显著的问题。重点阐述了创新实践基地培养模式、研究生指导本科生的“传帮带”培养模式、基于“双导师制”的联合培养模式、基于新型教学资源和技术手段的多元化指导模式的优势,也指出了其在创新能力培养方面的不足。基于不足提出了建立更科学的培养制度建设方向,主要包括创新实践课程体系构建,毕业设计选题的标准化与过程管理的规范化,探索审核与评价标准改革等方面。

关键词：新工科本科毕业设计论文质量创新能力培养实践教学

Fabrication and characterization of multi-scale coated boron powders with improved combustion performance:A brief review

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Defence Technology（防务技术） 2024年第1期31卷 27-40页

作者： Rui Liu Danfeng yang Kunyu Xiong Ying-Lei Wang qi-long yan Science and Technology on Combustion Internal Flow and Thermo-structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China Xi'an Modern Chemistry Research Institute Xi'an710065China

Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion *** literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal *** techniques include recrystallization,dual-solvent,phase transfer,electrospinning,*** one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron *** comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed *** and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature.

关键词： Boron powder coating Structure and morphology Condensed phase thermal reaction Ignition and combustion

Neodymium Organic Sulfonate Complexes: Tunable Electronegativity/Steric Hindrance and Application in Controlled Cis-1,4-polymerization of Butadiene

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Chinese Journal of Polymer Science 2019年第3期37卷 208-215页

作者： Jian-Yun He long Cui yan-long qi Quan-Quan Dai Chen-Xi Bai Key Laboratory of High-Performance Synthetic Rubber and its Composite Materials Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Rare earth catalysts possessing characteristics of cation-anion ion pair show advantages of adjusting electronegativity and steric hindrance of metal active sites, which can control the catalytic performance and stereoselectivity better than those of traditional metallocene and Ziegler-Natta catalysts in diene polymerization. In this work, a series of neodymium organic sulfonate complexes,Nd(CF_3SO_3)_3·x H_2O·y L(x, y: the coordination number; L refers to an organic electron donating ligand, such as acetylacetone(acac), isooctyl alcohol(IAOH), tributyl phosphate(TBP), etc.), have been synthesized to form the cationic active species in the presence of alkylaluminum such as Al(i-Bu)_3, AlEt_3, and Al(i-Bu)_2H, which display high activities and distinguishing cis-1,4 selectivities(up to99.9%) for the polymerization of butadiene. The microstructures, yield, molecular weight, and molecular weight distribution of the resulting polymer are well controlled by adjusting electronegativity/steric hindrance of the complexes. In addition, the kinetics, active species, and the possible process of polymerization are also discussed in this article.

关键词： Neodymium catalysts Organic sulfonate complexes Tunable electronegativity and steric hindrance Cis-1,4-polymerization Butadiene

Mechanism Exploration of Euphorbia fischeriana Steud. for Liver Cancer Based on Aspartic Acid Identification in Metabolomics

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Chinese Journal of Integrative Medicine 2024年第6期30卷 507-514页

作者： ZHAO Jing TIAN Xin-chen ZHANG Jia-qi HUANG Chen SUN yan qiAO Sen JIANG Shu-long Clinical Medical Laboratory Center Jining First People’s HospitalJiningShandong Province272000China Cheeloo College of Medicine Shandong UniversityJinan250000China

Objective:To investigate the anti-liver cancer effects and aspartic acid(Asp)-related action mechanism of Euphorbia fischeriana Steud.(LD).Methods:The mice model of liver cancer was established by injection of H22 *** 5 days,mice were randomly divided into model group,sorafenib group(20 mg/kg),LD high-dose(LDH,1.36 g/kg) group,LD medium-dose(LDM,0.68 g/kg) group,and LD low-dose(LDL,0.34 g/kg)group,10 mice each *** were intragastrically administered to the mice once daily for 10 days,*** weight,tumor size and tumor weight were *** index was *** changes of liver cancer tissues were evaluated by hematoxylin and eosin staining and TUNEL *** chromatography-mass spectrometer was used to analyze different metabolites between the model and LDH ***:After LD treatment,tumor weight,tumor size and hepatic index were reduced compared with the model *** and karyorrhexis of tumor cells were ***,61 differential metabolites(18 up-regulated,43 down-regulated) were affirmed and 20 pathways of KEGG(P<0.05) were *** addition,Bel-7402,HepG2 and H22 cell viabilities were significantly increased after adding Asp into the *** then,the cell proliferation effect induced by Asp was ameliorated by ***:The anti-liver cancer efficacy of LD extract was validated in H22 mice model,and inhibition of Asp level might be the underlying mechanism.

关键词： liver cancer Euphorbia fischeriana Steud. aspartic acid metabolomics

Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 7-12页

作者： Jian-qi Liu Zhi-qi Huang yan Su School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai 519082China

The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~*** the scenario of a low or moderate star formation efficiency,because massive neutrinos tend to suppress the growth of structure of the universe,the JWST observation tightens the upper bound of the neutrino *** A cold dark matter cosmology and a star formation efficiency∈[0.05,0.3](flat prior),we perform joint analyses of Planck+JWST and Planck+BAO+JWST,and obtain improved constraints∑m_(ν)<0.196 eV and ∑m_(ν)+<0.111 eV at 95% confidence level,*** on the above assumptions,the inverted mass ordering,which implies ∑m_(ν)≥0.1 eV,is excluded by Planck+BAO+JWST at 92.7% confidence level.

关键词： (cosmology:)cosmological parameters galaxies:abundances galaxies:formation neutrinos

Evaluating the thermal environment of urban land surfaces in Yakutsk,a city located in a region of continuous permafrost

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Advances in Climate Change Research 2024年第1期15卷 113-123页

作者： Xiang-long LI Ze ZHANG Jin-Xin LU Anatoli BROUCHKOV qing-Kai yan qi-Hao YU Sheng-Rong ZHANG Andrey MELNIKOV School of Civil Engineering and Transportation Institute of Cold Regions Science and EngineeringPermafrost InstituteNortheast Forestry UniversityHarbin150040China China Railway qinghai-Tibet Group Company Xining 810000China Department of Geocryology Faculty of GeologyLomonosov Moscow State UniversityMoscow 119234Russian Federation State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco Envi ronment and Re sourcesChinese Academy of SciencesLanzhou 730000China Melnikov Permafrost Institute Siberian BranchRussian Academy of ScienceYakutsk 677010Russian Federation

Rapid urbanization has led to changes in the urban land surface thermal ***,there are still much unknown about the urban land surface thermal conditions in permafrost *** is a unique geological environment,changes in the urban land surface thermal environment may trigger geological disasters caused by permafrost *** study utilized remote sensing data and geographic de-tectors to identify the dynamic changes in land surface temperature(LST)and land use/land cover(LU/LC)in Yakutsk,as well as the potential factors contributing to LST *** 1992 and 2020,the built-up area in Yakutsk increased by 36%,and the annual average LST in Yakutsk has risen by 6.67℃,accompanied by an expansion of high-temperature *** ongoing greening efforts,rapid urbanization poses a threat to these green *** in the normalized difference built-up index(NDBI)and land use transfer(LDT)were identified as the primary drivers of urban LST *** integrating geographic detector technology and artificial neural network models,we optimized the selection of input factors in the prediction model and used it to explore the future changes in LST in *** average LST in Yakutsk is expected to reach 23.4℃ and 25.1℃ in 2030 and 2040,respectively,with a further increase in high-temperature *** study provides a reference for ecological,hydrological,and geological assessments of cities in permafrost regions.

关键词： Remote sensing Land surface temperature Land use/Land cover Permafrost Yakutsk

Effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on viscosity and structure of slag for pyrometallurgical processing of spent automotive catalysts

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Journal of Iron and Steel Research(International) 2024年第3期31卷 608-621页

作者： Zhe Wang qi-long Wei Cheng-bin Shi Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was *** results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and ***,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of *** increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the *** slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin qi-chi Le yan-chao Jiang Da-zhi Zhao qi-yu Liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

An aqueous BiI_(3)-Zn battery with dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox

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Journal of Energy Chemistry 2024年第2期89卷 670-678,I0014页

作者： qi Deng Fangzhong Liu Xiongwei Wu Changzhu Li Weibin Zhou Bei long State Key Laboratory of Utilization of Woody Oil Resource Key Laboratory of National Forestry and Grassland Administration on Utilization Science for Southern Woody Oil ResourcesHunan Provincial Key Laboratory of Oils&Fats Molecular Structure and FunctionHunan Academy of ForestryChangsha 410004HunanChina School of Chemistry Xiangtan UniversityXiangtan 411105HunanChina School of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410128HunanChina

The development of aqueous battery with dual mechanisms is now arousing more and more *** dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox bring unexpected ***,differing from previous studies using Zn I_(2)additive,this work designs an aqueous Bi I_(3)-Zn battery with selfsupplied I^(-).Ex situ tests reveal the conversion of Bi I_(3)into Bi(discharge)and Bi OI(charge)at the 1st cycle and the dissolved I^(-)in *** active I^(-)species enhances the specific capacity and discharge medium voltage of electrode as well as improves the generation of Zn dendrite and ***,the porous hard carbon is introduced to enhance the electronic/ionic conductivity and adsorb iodine species,proven by experimental and theoretical ***,the well-designed Bi I_(3)-Zn battery delivers a high reversible capacity of 182 m A h g^(-1)at 0.2 A g^(-1),an excellent rate capability with 88 m A h g^(-1)at 10 A g^(-1),and an impressive cyclability with 63%capacity retention over 20 K cycles at 10 A g^(-1).An excellent electrochemical performance is obtained even at a high mass loading of 6 mg cm^(-2).Moreover,a flexible quasi-solid-state Bi I_(3)-Zn battery exhibits satisfactory battery *** work provides a new idea for designing high-performance aqueous battery with dual mechanisms.

关键词： Aqueous BiI_(3)-Zn battery Dual mechanisms I^(-)-induced uniform zinc deposition Ultralong cyclic life Flexible quasi-solid-state battery