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China Petroleum processing & Petrochemical Technology 2024年第1期26卷 1-11页

作者： Li Huifeng Li Mingfeng Zhang Le Wang Wei Nie Hong National Energy r&d Center of Petroleum refining Technology SINOPEC Research Institute of Petroleum Processing Co.Ltd.Beijing 100083China

To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were ***,the correlation between the surface characteristics of four different alumina and the existing Mo species states was *** was found that the Mo equilibrium adsorption capacity can be used as a specific descriptor to quantitatively evaluate the changes in surface characteristics of different alumina.A lower Mo equilibrium adsorption capacity for alumina means weaker metal-support interaction and the loaded Mo species are easier to transform into ***,the Mo-O-Al bonds still exist at the metal-support *** introduction of cationic surfactant hecadecyl trimethyl ammonium bromide(CTAB)can further improve Mo species dispersion through electrostatic attraction with Mo anions and interaction of its alkyl chain with the alumina surface;meanwhile,the introduction of ethylenediamine tetraacetic acid(EdTA)can complex with Ni ions to enhance the Ni-promoting effect on ***,the NiMo catalyst designed using alumina with lower Mo equilibrium adsorption capacity and the simultaneous addition of EdTA and CTAB exhibits the highest hydrodesulfurization activity for 4,6-dimethyl dibenzothiophene because of its proper metal-support interaction and more well-dispersed Ni-Mo-S active phases.

关键词： alumina Mo equilibrium adsorption capacity organic functional groups metal-support interaction hydrodesulfurization

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review on Security defense Technology research in Edge Computing Environment

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Chinese Journal of Electronics 2024年第1期33卷 1-18页

作者： Ke SHANG Weizhen HE Shuai ZHANG National digital Switching System Engineering and Technological r&d Center

Edge computing, which achieves quick data processing by sinking data computing and storage to the network edge, has grown rapidly along with the Internet of things. The new network architecture of edge computing brings new security challenges. Based on this, this paper investigates the edge computing security literature published in recent years and summarizes and analyzes research work on edge computing security from different attack surfaces. We start with the definition and architecture of edge computing. From the attack surface between device and edge server, as well as on edge servers, the research describes the security threats and defense methods of edge computing. In addition, the cause of the attack and the pros and cons of defense methods is introduced. The challenges and future research directions of edge computing are given.

关键词： Cloud computing Systems architecture Computer architecture Network architecture data processing Security Servers

research on welding deformation control technology of battery electric vehicle framed aluminum body

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Progress in Natural Science:Materials International 2024年第1期34卷 108-121页

作者： Bo Liu Jian Yang Jia Li Xiaolin Liao Qin Yang Jinsheng Zhang Tiegang Hu Shuxun Jiang School of Mechanical Engineering University of Science and Technology Beijing Chongqing Industry Polytechnic College Global r&d Center Chongqing Changan Automobile Co. Ltd Farizon New Energy Commercial Vehicle group

The welding process of aluminum(Al) alloy car body has problems such as poor weld quality, low welding co-efficient, and large welding deformation. This paper mainly focuses on material accuracy design, lap structure design, simulation, and process manufacturing to break through the precision control problems caused by welding deformation of battery electric vehicle Al alloy car body. First, the 209 key functional dimensional chains of Al body-in-white are analyzed and decomposed to component and profile tolerance dimensions step by ***, the differences of vertical butt, bevel butt, and plug structures are studied and joint matching is implemented in a targeted manner. Subsequently, through welding deformation simulation analysis and welding sequence optimization, the body-in-white welding process and tooling fixtures are guided and designed to ensure that the dimensional accuracy of the Al body is controlled to ±2 mm in all aspects. Finally, the design of the whole vehicle arrangement of mechanical, human-machine, and major components is carried out, and an all-Al framed battery electric vehicle lightweight platform with different sizes and ranges is innovatively created. The difficulties such as the contradiction between power battery size and arrangement space, unreasonable arrangement position, and load distribution are solved.

关键词： Aluminum alloy Frame structure Welding deformation simulation dimensional accuracy control Battery electric vehicle lightweight platform

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel research(International) 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng Shen Hao Zhang dong Zhou Hang Su Central Iron and Steel research Institute Co. Ltd.Beijing 100081China Material digital r&d Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co *** effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were *** as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Inhibitory effect and mechanism of tannic acid against two starch digestive enzymes

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Food Quality and Safety 2024年第1期8卷 115-123页

作者：钟毓秀倪德让杨玉波李元一王莉田金虎杨帆叶兴乾 department of Food Science and Nutrition Zhejiang Key Laboratory for Agri-Food ProcessingFuli Institute of Food ScienceZhejiang R&D Centre for Food Technology and EquipmentZhejiang UniversityHangzhouChina Institute of Science and Technology Moutai GroupZunyiChina Key Laboratory of Industrial Microbial resources development Kweichow Moutai Co.Ltd.RenhuaiChina

Backgrounds:Tannic acid(TA),as a plant-derived phenolic substance,is involved in regulating the activity of starch digestive enzymes,but its underlying mechanism remains *** and results:In the present study,inhibition rate and inhibition kinetics assays were performed and confrmed that TA had a strong inhibitory effect on bothα-amylase andα-glucosidase with IC50 values of 0.1585 mg/mL and 0.00542 mg/mL,respectively,through a mixed inhibition *** secondary structures of both enzymes were confrmed to be modifed by TA through circular dichroism(Cd)*** quenching analysis revealed that the interaction between TA and two enzymes was a static process of pontaneous complex ***,molecular docking revealed that non-covalent bonds were the main interaction forces between TA and both ***:Thus,TA was a promising candidate for the inhibition of starch-digesting enzymes,and the present research provided insight into postprandial glucose regulation through polyphenols.

关键词： Tannic acid α-amylase α-glucosidase inhibition starch digestion.

Possibility and stabilizing effect of Mo clusters in the Ni-based single-crystal superalloy

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Communications in Theoretical Physics 2024年第8期76卷 189-194页

作者： Yiqun du Huixin Jin rongkai Kang Boya Zhang Han Wang Jianxin Zhang Key Laboratory for liquid–Solid Structural Evolution and processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University department of Materials Science and Technology Tokyo University of Science

Nickel-based single-crystal superalloys are crucial materials for the preparation of aero-engine turbine blades. Many solute elements are added to superalloys for strengthening. However, the relationship between the clustering behavior of solute atoms and the properties of nickel-based single-crystal superalloys is still unclear. Herein, we conduct first-principles calculations onγ phases with Mo-Mo and Mo-Mo-ru clusters to reveal the possibility and stabilizing mechanism of solute clusters. Introducing Mo lowers the total energy, binding energy, and formation energy of the γ phase due to the replacement of weak Ni-Ni interaction with strong Mo-Ni bonding. Note that the γ phase containing the Mo-Mo cluster is more stable than that containing a Mo single atom, possibly owing to a wide affecting range. The ru atom added to the γ phase can further boost system stability, and it tends to form a Mo-Mo-ru cluster. The stabilizing impact of the Mo-Mo-ru cluster is demonstrated to be the replacement of weak Ni-Mo interaction by the strong ru-Mo interaction, which may be derived from the enhanced d-orbital hybridization.

关键词： density functional theory solute cluster superalloys

recent Advances in deciphering the Mechanisms and Biological Functions of dNA demethylation

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Chinese Journal of Chemistry 2024年第6期42卷 645-651页

作者： Yang Feng Sheng-Jun Chen Bi-Feng Yuan Key Laboratory of Aquatic Product processing Ministry of Agriculture and Rural AffairsNational R&D Center for Aquatic Product ProcessingSouth China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhouGuangdong510300 China School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhanHubei430071 China

5-Methylcytosine (5mC) is a dynamic and reversible epigenetic modification in genomic dNA of higher *** has been well-established that the demethylation of 5mC occurs through the ten-eleven translocation (TET)-mediated oxidation of 5mC followed by thymine dNA glycosylase (TdG)-initiated base excision repair (BEr).recent findings also have identified an alternative pathway of dNA *** this pathway,TET enzymes directly oxidize 5mC to form 5-formylcytosine (5fC) or 5-carboxylcytosine (5caC).These modified bases can undergo direct deformylation or decarboxylation,***,dNA demethylation can also occur through the deamination of 5mC and 5hmC,resulting in the production of thymine and 5-hydroxymethyluracil (5hmU),*** dNA demethylation pathways possess critical functional implications and roles in biological *** recent Advances article will focus on the studies of mechanisms and biological functions of dNA demethylation,shedding light on the reversible nature of the epigenetic modification of 5mC.

关键词： Epigenetics dNA dNA methylation 5-Methylcytosine demethylation Mechanisms Biological functions C—C bond cleavage Mass spectrometry

Microstructure and Shear Properties Evolution of Minor Fe-doped SAC/Cu Substrate Solder Joint under Isothermal Aging

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1279-1290页

作者： Quanzhen Li Chengming Li Xiaojing Wang Shanshan Cai Jubo Peng Shujin Chen Jiajun Wang Xiaohong Yuan Jiangsu University of Science and Technology Zhenjiang212003China r&d Center Yunnan Tin Group(Holding)Co.LtdKunming650000China The 58 Research Institute of China Electronics Technology Group CorporationWuxi214100China Yunnan Precious Metals Lab Sino-Platinum Metals Co.LtdKunming650156China

different amounts of Fe(0.005,0.01,0.03,0.05,and 0.07 wt%)were added to SAC305 to study the shear behavior damage of Fe-doped SAC solder joints under thermal loading(170℃,holding time of 0,250,500,and 750 h).The results show that during isothermal aging at 170℃,the average shear force of all solder joints decreases with increasing aging time,while the average fracture energy first increases and then decreases,reaching a maximum at 500 *** Fe doping could both increase shear forces and related fracture energy,with the optimum Fe doping amount being 0.03 wt%within the entire aging *** is because the doping Fe reduces the undercooling of the SAC305 alloy,resulting in the microstructure refining of solder *** in turn causes the microstructure changing from network structure(SAC305 joint:eutectic network+β-Sn)to a single matrix structure(0.03Fe-doped SAC305 joint:β-Sn matrix+small compound particles).Specifically,Fe atoms can replace some Cu in Cu_(6)Sn_(5)(both inside the solder joint and at the interface),and then form(Cu,Fe)_(6)Sn_(5) compounds,resulting in an increase in the elastic modulus and nanohardness of the ***,the growth of Cu_(6)Sn_(5) and Cu_(3)Sn intermetallic compounds(IMC)layer are inhibited by Fe doping even after the aging time prolonging,and Fe aggregates near the interface compound to form FeSn_(2).This study is of great significance for controlling the growth of interfacial compounds,stabilizing the microstructures,and providing strengthening strategy for solder joint alloy design.

关键词： SAC305 solder Fe doping Shear mechanical behavior Isothermal aging Interfacial intermetallic compounds(IMC)

Effect of ellagitannin metabolites ellagic acid and urolithins A-d on the non-enzymatic glycation of human serum albumin and inhibiting mechanisms

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Food Science and Human Wellness 2024年

作者： Lu Zhang Chun-yan Peng Wen-na Zhou Fei-yan Lu Lin-ju Xu Qing-hui Wen Xing Xie Zong-cai Tu National r&d Center of Freshwater Fish processing College of Life Science Jiangxi Normal University State Key Laboratory of Food Science and resources Nanchang University

Effect of ellagitannins gut microbiota metabolites ellagic acid (EA) and urolithin A-urolithin d (UroA-Urod) on human serum albumin (HSA) glycation were firstly evaluated in this research. The inhibition mechanisms were investigated by methylglyoxal (MGO) trapping and radical scavenging ability assays， docking studies and Nano LC-Orbitrap-MS/MS technology. results indicated that the inhibition of urolithins on HSA glycation was highly positive correlated with the number of phenolic hydroxy groups. Addition of Urod and EA could effectively enhance the content of free amino group， suppress dicarbonyl compounds and advanced glycation end-products (AGEs) formation， alleviated tryptophan and protein oxidation， inhibited HSA amyloid-like aggregation. They could also trap MGO and scavenge dPPH· and ABTS·+. Molecular docking indicated that EA and UroA-Urod interact with HSA mainly through hydrogen bound and hydrophobic interaction， among which two or three hydrogen bonds were formed. The number of glycation sites were reduced from 11 to 10， 10， 7， and 10， respectively， when 90 μmol/L of EA， UroA， UroC and Urod were added. However， weak inhibition was observed on UroA and UroB. These findings can provide scientific evidence for the application of ellagitannins-rich foods in alleviating diabetic complications.

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Effect of sodium starch octenyl succinate-based Pickering emulsion on the physicochemical properties of hairtail myofibrillar protein gel subjected to multiple freeze-thaw cycles

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Food Science and Human Wellness 2024年第2期13卷 1018-1028页

作者： Huinan Wang Jiaxin Zhang Xinran Liu Jinxiang Wang Xuepeng Li Jianrong Li Key Laboratory of Food Nutrition and Safety Ministry of EducationCollege of Food Science and EngineeringTianjin University of Science and TechnologyTianjin 300457China College of Food Science and Technology Bohai UniversityNational R&D Branch Center of Surimi and Surimi Products ProcessingJinzhou 121013China

A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were *** whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(Praman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and *** an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the *** F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering *** findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs.

关键词： Pickering emulsion Myofibrillar protein Gel properties Freeze-thaw stability Intermolecular interactions

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