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Chinese Journal of Aeronautics 2024年第6期37卷 78-88页

作者： Siyi GUO Zhenli chen Xuanyu yao School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aero Engine Academy of China Beijing 101304China

Blended-Wing-Body(BWB)aircraft is promoted as one of the most possible layouts to achieve more sustainable civil *** to the non-circular cross-section of the center-body,a bulge deformation forms over the upper surface of the body under the coupled loads of the internal pressurization of the cabin and the aerodynamic bending moments of the wing,which reduces the lift-to-drag ratio of BWB *** a limited deformation,the relationship between the aerodynamic performance and the structural weight needs to be *** this work,the effects of stiffness constraints on the center-body deformation,structural weight of the airframe and aerodynamic performance were investigated by using an analytical model of the Pultruded Rod Stitched Efficient Unitized Structure(PRSEUS)for the airframe and the computational fluid dynamics method,*** results show that as the stiffness constraint increases,the spacings between the rod stringers and the frame stiffeners decrease,and the structural weight increases inversely.A 5.2% reduction of the lift-to-drag ratio is encountered at cruise for a medium deformation design of 42.8 mm/m.A higher aerodynamic penalty is suffered when the stiffness constraint is further *** final deformation criterion is different when the weight vector of the aerodynamic performance and structural weight is different.

关键词： Blended-Wing-Body(BWB) Deformation PultrudedRod Stitched Effi-cient Unitized Structure(PRSEUS) Cabin structure Stiffness constraint

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

作者： Gu-jun chen Sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

Quantum Curve and Bilinear Fermionic Form for the Orbifold Gromov–Witten Theory of P[r]

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Acta Mathematica Sinica,English Series 2024年第1期40卷 43-80页

作者： Chong yao chen Shuai GUO Mathematics Department Duke UniversityBox 90320DurhamNC 27708-0320USA School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

We construct the quantum curve for the Baker-Akhiezer function of the orbifold Gromov-Witten theory of the weighted projective line P[r].Furthermore,we deduce the explicit bilinear Fermionic formula for the(stationary... 详细信息

关键词： Quantum curve Free Fermions Gromov-Witten invariants Orbifold P^(1)

Deformation-based longitudinal equivalent stiffness beam model for shield tunnel and its application in seismic deformation method

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Underground Space 2024年第4期17卷 280-299页

作者： pingliang chen ping Geng Junbo chen Qi Yang Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Intelligent Geotechnics and Tunnelling Chengdu 610031China Technology Center of Sichuan Road&Bridge Group Co. LtdChengdu 610041China

In the longitudinal seismic deformation method for shield tunnels,one of the most commonly used is the longitudinal equivalent stiffness beam model(LES)for simulating the mechanical behavior of the *** this model,axial deformation and bending deformation are independent,so the equivalent stiffness is a constant ***,the actual situation is that axial deformation and bending deformation occur simultaneously,which is not considered in *** present,we are not clear about the effect on the calculation results when axial deformation and bending deformation occur ***,in this paper,we improve the traditional LES by taking the relative deformation as a load and considering the coordinated deformation of axial and bending degrees of *** improved model is called DNLES,and its neutral axis equations are an explicit ***,we propose an iterative algorithm to solve the calculation model of the DNLES-based longitudinal seismic deformation *** a calculation example,we find that the internal forces based on LES are notably underestimated than those of DNLES in the compression bending zone,while are overestimated in the tension bending *** considering the combined effect,the maximum bending moment reached 13.7 times that of the LES model,and the axial pressure and tension were about 1.14 and 0.96 times,*** analysis reveals the coordinated deformation process in the axial and bending directions of the shield tunnel,which leads to a consequent change in equivalent *** explains why,in the longitudinal seismic deformation method,the traditional LES may result in unreasonable calculation results.

关键词： Shield tunnel Longitudinal seismic deformation method Longitudinal equivalent stiffness beam Combined axial and bending deformation

Comparison of biliary protein spectrum in gallstone patients with obesity and those with normal body weight

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 385-392页

作者： Min-Zhi chen ping Xie Xiao-Chang Wu Zhen-Hua Tan Hai Qian Zhi-Hong Ma Xing yao Department of Hepatopancreatobiliary Surgery Huzhou Central HospitalAffiliated Huzhou HospitalZhejiang University School of MedicineHuzhou 313000China Huzhou Key Laboratory of Molecular Medicine Huzhou Central HospitalAffiliated Huzhou HospitalZhejiang University School of MedicineHuzhou 313000China

Background: Obesity is a common public health issue and is currently deemed a disease. Research has shown that the risk of gallstones in individuals with obesity is elevated. This study aimed to explore the bile proteomics differences between cholelithiasis patients with obesity and normal body weight. Methods: Bile samples from 20 patients(10 with obesity and 10 with normal body weight) who underwent laparoscopic cholecystectomy at our center were subjected to tandem mass tag labeling(TMT) and liquid chromatography-tandem mass spectrometry(LC-MS/MS), followed by further bioinformatic analysis. Results: Among the differentially expressed proteins, 23 were upregulated and 67 were downregulated. Bioinformatic analysis indicated that these differentially expressed proteins were mainly involved in cell development, inflammatory responses, glycerolipid metabolic processes, and protein activation cascades. In addition, the activity of the peroxisome proliferator-activated receptor(PPAR, a subfamily of nuclear receptors) signaling pathway was decreased in the Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis. Two downregulated proteins in the PPAR signaling pathway, APO A-Ⅰ and APO A-Ⅱ, were confirmed using enzyme-linked immunosorbent assay. Conclusions: The PPAR signaling pathway may play a crucial role in the development of cholelithiasis among patients with obesity. Furthermore, biliary proteomics profiling of gallstones patients with obesity is revealed, providing a reference for future research.

关键词： Proteome profiling Gallstones Obesity-associated gallstones Tandem mass tag labeling PPAR signaling

Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source

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Journal of Ocean University of China 2024年第1期23卷 247-254页

作者： LIU yao chen Yifan GE Changzi Marine College Shandong UniversityWeihai 264209China

The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying *** and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of ***,biodeposition in cage culture areas without specific emission rules can be simplified as point source *** is a fluid simulation software that can simulate the dispersion of particulate matter simply and *** on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid *** the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling *** sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),*** simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),*** was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well ***,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative ***,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition i

关键词： fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation

Discrete Approximation and Convergence Analysis for a Class of Decision-Dependent Two-Stage Stochastic Linear Programs

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Journal of the Operations Research Society of China 2024年第3期12卷 649-679页

作者： Jie Jiang Zhi-ping chen College of Mathematics and Statistics Chongqing UniversityChongqing401331China School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049ShaanxiChina Center for Optimization Technique and Quantitative Finance Xi’an International Academy for Mathematics and Mathematical TechnologyXi’an710049ShaanxiChina

Customary stochastic programming with recourse assumes that the probability distribution of random parameters is independent of decision *** studies demonstrated that stochastic programming models with endogenous uncertainty can better reflect many real-world activities and applications accompanying with decision-dependent *** this paper,we concentrate on a class of decision-dependent two-stage stochastic programs(DTSPs)and investigate their discrete *** develop the discrete approximation methods for DTSPs,we first derive the quantitative stability results for *** on the stability conclusion,we examine two discretization schemes when the support set of random variables is bounded,and give the rates of convergence for the optimal value and optimal solution set of the discrete approximation problem to those of the original *** we extend the proposed approaches to the general situation with an unbounded support set by using the truncating *** an illustration of our discretization schemes,we reformulate the discretization problems under specific structures of the decision-dependent ***,an application and numerical results are presented to demonstrate our theoretical results.

关键词： Stochastic programming Decision-dependence Discrete approximation Stability Convergence rate

Electron-transporting boron-doped polycyclic aromatic hydrocarbons:Facile synthesis and heteroatom doping positions-modulated optoelectronic properties

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Chinese Chemical Letters 2024年第4期35卷 447-451页

作者： Tingting Huang Zhuanlong Ding Hao Liu ping-An chen Longfeng Zhao Yuanyuan Hu Yifan yao Kun Yang Zebing Zeng Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Shenzhen Research Institute of Hunan University Shenzhen 518000China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education and Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and Electronics Hunan UniversityChangsha 410082China

While heteroatom doping serves as a powerful strategy for devising novel polycyclic aromatic hydrocarbons(PAHs), the further fine-tuning of optoelectronic properties via the precisely altering of doping patterns remains a challenge. Herein, by changing the doping positions of heteroatoms in a diindenopyrene skeleton, we report two isomeric boron, sulfur-embedded PAHs, named Anti-B_(2)S_(2) and Syn-B_(2)S_(2), as electron transporting semiconductors. Detailed structure-property relationship studies revealed that the varied heteroatom positions not only change their physicochemical properties, but also largely affect their solid-state packing modes and Lewis base-triggered photophysical responses. With their low-lying frontier molecular orbital levels, n-type characteristics with electron mobilities up to 1.5 × 10^(-3)cm^(2)V^(-1)s^(-1)were achieved in solution-processed organic field-effect transistors. Our work revealed the critical role of controlling heteroatom doping patterns for designing advanced PAHs.

关键词： Polycyclic aromatic hydrocarbon Optoelectronic properties Heteroatom doping n-Type organic semiconductors Structure–property relationship

Preparation of calcium carbonate with microstructure and nanostructure from carbide slag for CO_(2) sequestration by using recyclable ammonium chloride

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Particuology 2024年第7期90卷 1-9页

作者： Jin yao Qiuju chen Li Zeng Wenjin Ding Key Laboratory of Ministry of Education for Solid Waste Treatment and Resource Recycle Southwest University of Science and TechnologyMianyang621010China Sichuan Engineering Lab of Non-metallic Mineral Powder Modification and High-value Utilization Mianyang621010China School of Architecture and Civil Engineering Chengdu UniversityChengdu610106China

Based on the composition characteristics of carbide slag and the application of polyvinyl chloride,a method of preparing calcium carbonate with microstructure and nanostructure by using carbide slag as a raw material and ammonium chloride as a leaching agent was *** factors for the preparation of calcium carbonate and the effects of different conditions on the crystal phase,grain size,and morphology of calcium carbonate were systematically *** results showed that the nanosized calcium carbonate was prepared at 60 mL/min,25°C,no additional ammonia,and 60 *** product of spherical vaterite was in accordance with the relevant standards for the industrial precipitation of calcium ***,the reuse of carbonation filtrate was *** crystal phase,grain size,and morphology of the carbonation product could be controlled by adjusting the reaction *** manuscript provided a new idea for resource utilization of carbide slag and preparing nanocalcium carbonate.

关键词： Carbide slag Ammonium chloride Cyclic utilization Micro and nano structure Product control