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Patterning single-layer materials by electrical breakdown using atomic force microscopy

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Nanotechnology and Precision Engineering 2024年第1期7卷 71-77页

作者： yajie Yang Jiajia Lu Yanbo Xie Libing Duan School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics and Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China

The development of nanoelectronics and nanotechnologies has been boosted signiﬁcantly by the emergence of 2. materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2. materials is critical for assembling *** here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on *** can be achieved by voltage scanning or applying a constant voltage while moving the *** measuring the electrical current,the formation process on single-layer materials was shown *** present results provide evidence of successful pattern fabrication on single-layer MoS2.boron nitride,and graphene,although further conﬁrmation is still *** proposed method holds promise as a general nanomachining technology for the future.

关键词： 2. material Nanopattern AFM Electrical breakdown Lithography

Bifurcations,chaos analysis and control in a discrete predator-prey model with mixed functional responses

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International Journal of Biomathematics 2024年第3期17卷 185-210页

作者： yajie Sun Ming Zhao Yunfei Du School of Science China University of Geosciences(Beijing)Beijing100083P.R.China School of Basic Education Beijing Institute of Graphic Communication Beijing102600P.R.China

Many discrete systems have more distinctive dynamical behaviors compared to continuous ones,which has led lots of researchers to investigate *** discrete predatorprey model with two different functional responses(Holling type I and II functional responses)is discussed in this paper,which depicts a complex population *** local dynamical behaviors of the interior fixed point of this system are *** detailed analysis reveals this system undergoes flip bifurcation and Neimark-Sacker ***,we prove the existence of Marotto's chaos by analytical *** addition,the hybrid control method is applied to control the chaos of this *** simulations are presented to support our research and demonstrate new dynamical behaviors,such as period-10,19,2.,39,48 orbits and chaos in the sense of Li-Yorke.

关键词： Predator-prey model flip bifurcation Neimark-Sacker bifurcation Marotto's chaos chaos control

Operational requirements analysis method based on question answering of WEKG

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Journal of Systems Engineering and Electronics 2024年第2期35卷 386-395页

作者： ZHANG Zhiwei DOU yajie XU Xiangqian MA Yufeng JIANG Jiang TAN Yuejin College of Systems Engineering National University of Defense TechnologyChangsha 410073China

The weapon and equipment operational requirement analysis(WEORA) is a necessary condition to win a future war,among which the acquisition of knowledge about weapons and equipment is a great challenge. The main challenge is that the existing weapons and equipment data fails to carry out structured knowledge representation, and knowledge navigation based on natural language cannot efficiently support the WEORA. To solve above problem, this research proposes a method based on question answering(QA) of weapons and equipment knowledge graph(WEKG) to construct and navigate the knowledge related to weapons and equipment in the WEORA. This method firstly constructs the WEKG, and builds a neutral network-based QA system over the WEKG by means of semantic parsing for knowledge navigation. Finally, the method is evaluated and a chatbot on the QA system is developed for the WEORA. Our proposed method has good performance in the accuracy and efficiency of searching target knowledge, and can well assist the WEORA.

关键词： operational requirement analysis weapons and equipment knowledge graph(WEKG) question answering(QA) neutral network

Biomineralization of soil with crude soybean urease using different calcium salts

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1788-1798页

作者： yajie Weng Junjie Zheng Hanjiang Lai Mingjuan Cui Xingzhi Ding School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan430074China Zijin School of Geology and Mining Fuzhou UniversityFuzhou350108China College of Civil Engineering Fuzhou UniversityFuzhou350116China

Calcium salt is an important contributing factor for calcium-based *** study the effect of calcium salt on soil biomineralization using crude soybean urease,the calcium salts,including the calcium chloride (CaCl_(2.),calcium acetate ((CH_(3)COO)_(2.Ca) and calcium nitrate (Ca(NO_(3))_(2.),were used to prepare the biotreatment solution to carry out the biomineralization tests in this *** series of biomineralization tests in solution and sand column,respectively,were *** electron microscopy (SEM) and X-ray diffraction (XRD) were performed to determine the microscopic characteristics of the precipitated calcium carbonate (CaCO_(3)) *** experimental results indicate that the biomineralization effect is the best for the CaCl2.case,followed by (CH_(3)COO)_(2.Ca,and worst for Ca(NO_(3))_(2. under the test conditions of this study (i.e.1 mol/L of calcium salt-urea).The mechanism for the effect of the calcium salt on the biomineralization of crude soybean urease mainly involves: (1) inhibition of urease activity,and (2. influence on the crystal size and morphology of CaCO_(3).Besides Ca^(2.) ,the anions in solution can inhibit the activity of crude soybean urease,and NO_(3)− has a stronger inhibitory effect on the urease activity compared with both CH_(3)COO^(−) and Cl^(−) .The co-inhibition of Ca^(2.) and NO_(3)− on the activity of urease is the key reason for the worst biomineralization of the Ca(NO_(3))_(2. case in this *** difference in biomineralization between the CaCl_(2. and (CH_(3)COO)_(2. Ca cases is strongly correlated with the crystal morphology of the precipitated CaCO_(3).

关键词： Biomineralization Crude soybean urease Calcium salt Influence mechanism

Creep damage evolution process of asphalt binder based on viscoelastic characteristics

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 497-506页

作者： Xiaofei Qi Shuang Tian Liyan Shan Shuang Liu yajie Wang School of Transportation Science and Engineering Harbin Institute of TechnologyHarbin 150090China College of Water Conservancy&Architectural Engineering Shihezi UniversityShihezi 832003China

The creep damage evolution of asphalt binder plays a significant role in investigating the formation mechanism of *** rutting is the common distress at high temperatures for asphalt ***,the reliability of existing creep damage parameters is under questioned,and these parameters cannot accurately illustrate the change of intrinsic microstructure for asphalt *** this paper,a new test protocol was given access to study the evolution of viscoelastic parameters during creep *** was completed by inserting the frequency sweep during creep *** frequency sweep curve clusters were fitted by the generalized Kelvin-Voigt model for obtaining the change law of model *** on the change law and sensitivity analysis of model parameters,(E_(2.+E_(3))/2.was proposed as the creep damage *** to the curve of(E_(2.+E_(3))/2.versus loading time,two stages during the creep test could be identified:an approximate constant value in phase I and a linear decrease in phase *** differences about creep property of binders could be determined by this new proposed *** results not only ensure better understanding of the creep damage mechanism of binders,but also lay the theoretical foundation on predicting the anti-rutting performance of binders.

关键词： Asphalt binder Multi-stage creep test Damage variable Evolution law

A combination of straw incorporation and polymer-coated urea offsets soil ammonia and nitrous oxide emissions in winter wheat fields

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Journal of Integrative Agriculture 2024年第5期23卷 1718-1736页

作者： Xiaoyun Wang yajie Tian Qianhui Zhang Zhengxin Zhao Rui Wang Huanjie Cai Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F UniversityYangling712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2.O)emissions from agricultural fields have not been comprehensively evaluated in Northwest *** conducted a two-year field experiment to assess the effects of combining SI with either uncoated urea(U)or PCU on soil NH_(3)emissions,N_(2.O emissions,winter wheat yields,yield-scaled NH_(3)(/NH_(3)),and yield-scaled N_(2.O(/N_(2.O).Five treatments were investigated,no nitrogen(N)fertilizer(N_(0)),U application at 150 kg N ha-1 with and without SI(SI+U and S_(0)+U),and PCU application at 150 kg N ha^(-1) with and without SI(SI+PCU and S_(0)+PCU).The results showed that the NH_(3);emissions increased by 2..98-34.35%following Sl compared to straw removal,mainly due to increases in soil ammonium(NH_(4)^(+)-N)content and water-flled pore space(WFPS).SI resulted in higher N_(2.O emissions than under the So scenario by 13.31-49.2.%due to increases in soil inorganic N(SIN)contents,WFPS,and soil microbial *** contrast,the PCU application reduced the SIN contents compared to the U application,reducing the NH_(3)and N_(2.O emissions by 45.99-58.07 and 18.08-53.04%,***,no significant positive effects of the SI or PCU applications on the winter wheat yield were *** lowest /NH_(3) and /N_(2.O values were observed under the S_(0)+PCU and SI+PCU *** results suggest that single PCU applications and their combination with straw are the optimal agricultural strategies for mitigating gaseous N emissions and maintaining optimal winter wheat yields in Northwest China.

关键词： straw incorporation polymer-coated urea NH_(3)and N_(2.O emissions winter wheat yields

Toward Selective Synthesis of Protein Olympiadanes via Orthogonal Active Templates in One Step

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CCS Chemistry 2024年第4期6卷 1047-1059页

作者： Fan Zhang yajie Liu Xiao-Di Da Wen-Bin Zhang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871 Beijing Academy of Artificial Intelligence Beijing 100084

Unlike small molecules,the topological complexity of macromolecules remains largely unexplored due to the huge synthetic ***,we report the development of orthogonal active templates for concise and selective synthesis of protein[n]heterocatenanes toward protein *** active template(AT-Snoop)was first developed based on the isopeptide-bond-forming RrgA domain with comparable efficiency and excellent orthogonality to the previously reported active template(AT-Spy)based on the CnaB2.*** combination facilitated the selective synthesis of protein[n]catenanes from multiple components in one step and the resulting structures were verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis,size exclusion chromatography,liquid chromatography-mass spectrometry,and proteolytic digestion *** results offered a promising solution to tackling the daunting challenge of precision synthesis of protein olympiadane with five distinct ring *** only did the success provide new tools for proteintopology engin eering but alsospurred and fueled the future exploitation of topology-related functional benefits in protein science.

关键词： catenane topology active template SnoopTag SnoopCatcher SpyTag SpyCatcher

FCF-LDH/BiVO_(4)with synergistic effect of physical enrichment and chemical adsorption for efficient reduction of nitrate

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Green Energy & Environment 2024年第7期9卷 1112-1121页

作者： yajie Bai Zhenyuan Fang Yong Lei Lijing Liu Huaiquan Zhao Hongye Bai Weiqiang Fan Weidong Shi School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang212013China Institute of Physics&IMN MacroNano Technische Universitat IlmenauIlmenau98693Germany School of Chemistry Beihang UniversityBeijing100191China

Photoelectrochemical NO_(3)^(-)reduction(PEC NITRR)not only provides a promising solution for promoting the global nitrogen cycle,but also converts NO_(3)^(-)to the important chemicals(NH_(3)).However,it is still a great challenge to prepare catalysts with excellent NO_(3)^(-)adsorption/activation capacity to achieve high ***,we designed a novel Fe^(2.)~Cu^(2.)Fe^(3+)LDH/BiVO_(4)(FCF-LDH/BVO)catalyst with synergistic effect of chemical adsorption and physical ***^(2.)in FCF-LDH/BVO provides the rich Lewis acid sites for the adsorption of NO_(3)^(-),and the appropriate layer spacing of FCF-LDH further promotes the physical enrichment of NO_(3)^(-)in its interior,thus realizing the effective contact between NO_(3)^(-)and active sites(Fe^(2.)).FCF-LDH/BVO showed excellent NH_(3)production performance(FE_(NH_(3))=66.1%,r_(NH_(3))=13.8μg h^(-1)cm^(-2.)and selectivity(FE_(NO_(2.^(-))=2.5%,r_(NO_(2.^(-))=4.9μg h^(-1)cm^(-2.)in 0.5 mol L^(-1)Na_(2.SO_(4)*** addition,FCF-LDH/BVO maintains the desirable PEC stability for six cycle experiments,showing great potential for practical ***^(14)NO_(3)^(-)and^(15)NO_(3)^(-)isotope test provides strong evidence for further verification of the origin of N in the generated NH_(3).This LDH catalyst has a great potential in PEC removal of NO_(3)^(-)from groundwater.

关键词： LDH Lewis acid sites Physical enrichment Photoelectrochemical NO_(3)^(-)Reduction Ammonia

Active Template Synthesis of Protein[n]Catenanes Using Engineered Peptide–Peptide Ligation Tools

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CCS Chemistry 2024年第2期6卷 377-389页

作者： Fan Zhang yajie Liu Yu Shao Wen-Bin Zhang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 Beijing Academy of Artificial Intelligence Beijing 100084

The expansion of protein topological diversity requires new and efficient synthetic ***,we report the second and third generations of the SpyStapler-mediated SpyTag/BDTag ligation system for the efficient synthesis of 4-arm star proteins and the repurposing of the third generation as an active template to enable the synthesis of higher-order protein[n]catenanes(n=3,4,and 5).SpyStapler003 has a higher affinity to its cognate SpyTag and BDTag reactive pairs relative to the original ***,it can overcome much more profound steric hindrance in protein ligation and improve the efficiency of the resulting active template tool to facilitate the construction of radial protein[n]*** proteins of interest,such as dihydrofolate reductase and the nanobody KN035,can be modularly incorporated into the[n]catenanes with intact *** of passive and active template strategies gives rise to linear protein[4]catenanes,which further expands the current topological ***,higher-order protein catenation not only leads to enhanced thermal stability and proteolytic resistance but also higher affinity of the nanobody via multivalent *** study provides tools useful for bioconjugation and new topological protein scaffolds for the multivalent display of enzymes and antibodies.

关键词： SpyTag SpyCatcher catenane topology active template ligation