The detection of crane braking descent distance faces numerous challenges in practical engineering applications, primarily due to limitations in the measurement accuracy of existing detection equipment, the complexity of on?site operations, and high equipment costs. A method is proposed to obtain the braking descent distance by using inertial sensors to collect acceleration and angular velocity data during the crane braking process, performing attitude calculation, and combining it with a double integration algorithm. First, a Lagrangian dynamic model of the crane is established to analyze the coupling relationship between the braking descent distance and the equipment environment. Second, a data acquisition device is designed, the detection steps are described, and data synchronous transmission is employed to enhance signal reliability. Finally, the data processing method is investigated, a complete data processing workflow is designed, complex integration algorithms are compared and analyzed, and practical feasibility is verified. The results indicate that this detection method can prevent serious accidents such as load dropping caused by insufficient braking performance, offering superior comprehensive performance, strong feasibility, and promising market prospects.
Medical image segmentation serves as a pivotal technology in computer vision, particularly capable in providing critical diagnostic information when processing multi?modal medical images like CT and MRI. However, existing techniques still exhibit significant limitations in modality collaborative modeling, precise structural boundary representation, and effective integration of multi?scale semantic information. To address these challenges, this paper proposes MicFormer?HMD, an enhanced architecture that improves upon the traditional MicFormer framework.A Hybrid Gating Module is designed to achieve dynamic feature selection before Cross?Modal interaction through parameterized convolutions and gating functions, enabling adaptive noise suppression and enhances discriminative feature representation. Then, we develop a Multi?Branch Fusion Attention module that employs a Multi?Branch dilated convolution architecture and a dual attention calibration mechanism,significantly improving the model's capability in capturing and integrating multi?scale contextual information. Dynamic Snake Convolution is incorporated, whose deformable kernels adaptively conform to the complex morphology of cardiac anatomical structures, thereby strengthening geometric perception. The proposed MicFormer?HMD architecture demonstrates remarkable advantages in cardiac image segmentation tasks, showing particular improvements in maintaining thin?walled tissue continuity and complex vascular connectivity.
To address the challenges in LNG cold energy utilization and waste heat recovery from gas turbine flue gas, and to facilitate the liquefaction of the contained carbon dioxide, a novel combined cooling, heating and power (CCHP) system is proposed. The effects of the split ratio (x), the compressor inlet pressure（p25),and the mass fraction of carbon tetrafluoride in the mixed working fluid (w) were analyzed. A multi?objective optimization was subsequently performed using a genetic algorithm. The results show that decreasing x and increasing w enhances thermal efficiency, exergy efficiency,and net output work,while reducing the average unit cost.The optimal compressor inlet pressure (p25) was found to be in the range of 8.0 MPa to 9.0 MPa. The thermal efficiency, exergy efficiency, the average unit cost and the average unit cost under the optimal working conditions of the system were 67.62%, 56.98% and 22.11 $/GJ，respectively.
Damage to insulation layer of buried oil pipelines will significantly change the distribution of the soil temperature field around the pipeline,thereby affecting the thermal performance and operational safety of the pipeline.Based on the theory of multi-physics field coupling,this study establishes a three-dimensional steady-state heat transfer model to quantitatively analyze the temperature drop characteristics of the pipeline and the evolution law of the soil temperature field under different soil types(clay,loam,sand).The model was solved using ANSYS Fluent 2022,with the effect of moisture intrusion considered.The numerical simulation results show that in sand soil,the critical number of segments with complete insulation damage is 15 segments(each 100 meters),corresponding to a critical damage distance of 1.5 kilometers.According to this critical distance,initial monitoring points are set,and a total of 56 monitoring points are required for an 80-kilometer pipeline.The temperature at each monitoring point shows a non-linear decreasing trend along the pipeline.The outlet temperature at the 28th monitoring point(42 kilometers away)drops to the wax precipitation point of 45℃for the first time.The"critical distance segmented monitoring method"proposed in this study can achieve accurate monitoring of the pipeline damage status in the sand soil section,providing technical support for the safe operation of the pipeline.
The tubular heating furnace is a key heating unit and a major energy consumer in refinery and chemical plants.Improving fuel combustion efficiency and the thermal efficiency of the heating furnace is of practical significance for energy conservation and emission reduction in these facilities. In this paper, the tubular heating furnace of aviation kerosene hydrofining unit is studied. The computational fluid dynamics (CFD) simulation method is adopted, and the standard k?ε turbulence model, component transport combustion model and P?1 radiation model are used. The temperature of the furnace, the average temperature of the surface of the furnace tube and the temperature distribution of the burner were investigated by changing the oxygen content of the combustion air. The results indicate that when the oxygen volume fraction changes in the range of 18.55%-26.00%, the oxygen volume fraction change has a significant impact on the temperature field and combustion efficiency in the furnace, and the existing radiation chamber, furnace tube and burner fully meet the needs of oxygen?rich combustion..
This study theoretically investigates the electronic structures and photophysical properties of isomeric triangular macrocyclic gold(I)?biphenylene complex (MPP) using quantum chemical calculations and wavefunction analysis methods，aiming to elucidate the physical mechanisms underlying their linear and nonlinear optical spectra.The molecular orbital characteristics were analyzed via highest occupied molecular orbital (HOMO)?lowest unoccupied molecular orbital (LUMO) analysis，density of states (DOS)，one?photon absorption (OPA) spectrum，as well as static and 280 nm resonance Raman spectra， thereby revealing the regulatory mechanisms of electronic excitation features and molecular vibrations on linear spectral properties. The electron excitation characteristics of MPP were further visualized using charge difference density (CDD) maps and transition density matrix (TDM)，clarifying the influence of charge transfer and localized excitations on optical responses.Additionally，the core physical features of nonlinear optical behaviors were characterized by computing molecular (hyper)polarizability to explore its nonlinear optical response patterns.Results demonstrate that MPP exhibits a strong absorption peak at 280 nm in linear spectra， with molecular vibrational modes significantly modulating Raman spectral features.In nonlinear optical aspects，MPP shows pronounced nonlinear anisotropic characteristics，and the (hyper)polarizability decreases with increasing wavelength.
Semiconductor doping can promote the photoelectrocatalytic application of semiconductor materials by constructing impurity energy levels and reducing the band gap.In this paper,we designed a preparation method for metal-doped semiconductor materials.The transition metal Co was combined with the anionic ligand of the metal-organic framework(MOF)MIL-125 through coordination.Then,the Co-doped TiO2 was obtained through pyrolysis,and its performance in photocatalysis was studied.The results showed that the co-doped TiO2 exhibits a high photocurrent density(9.87 μA/cm2),which is 3.8 times of the undoped TiO2.Meanwhile,the degradation reaction rate constant also significantly increases from 0.041 min⁻¹ before doping to 0.063 min⁻¹ after doping.The incorporation of Co species not only extends the visible-light absorption edge of TiO2 but also introduces well-defined impurity energy levels within its bandgap,thereby facilitating efficient separation and migration of photogenerated charge carriers while significantly suppressing electron-hole recombination.
Amid global energy transition, electrical pulse fracturing has emerged as a key technology for environmentally sustainable development of unconventional oil and gas resources,as it uses controllable shockwaves generated by high?voltage pulse discharge to construct multi?scale fracture networks and achieve efficient rock fragmentation. This study focuses on the rock?breaking mechanisms and numerical simulation of electrical pulse fracturing. The principles of pulse discharge and energy conversion processes are systematically analyzed, with an equivalent model established between discharge?induced shockwaves and TNT explosion shockwaves. The fracturing mechanisms?including shear, cavitation, tensile effects are elucidated for sandstone and shale reservoirs, and the attenuation of fracturing efficacy with increasing distance is quantitatively evaluated. Using TNT explosion simulations performed on the Autodyn platform and damage monitoring in sandstone and shale, lithological parameters are found to critically govern shockwave energy attenuation paths and damage patterns. Specifically,sandstone reservoirs require pulse energy optimization to activate multidirectional fracture networks, whereas shale reservoirs call for distance modulation to guide the propagation of dominant fractures.
A zirconium oxychloride(ZOC)-based deep eutectic solvent(DES)was successfully prepared through thermal mixing of ethylene glycol(EG)with ZOC.The structure of the DES was systematically characterized using FT-IR and ¹H NMR,confirming its successful synthesis,while its viscosity was determined using a rotational viscometer.An extraction-oxidation coupled desulfurization system was constructed using hydrogen peroxide as the oxidant and the DES as both an extractant and a catalyst.The effects of DES composition,reaction temperature,oxygen-to-sulfur molar ratio,solvent-to-oil mass ratio,and different types of sulfides on the desulfurization rate were systematically investigated.The results demonstrated that under optimal conditions(zirconyl chloride to ethylene glycol molar ratio of 1∶24,reaction temperature of 50℃,solvent-to-oil mass ratio of 1∶5,and oxygen-to-sulfur molar ratio of 8),the system achieves a desulfurization rate of 99.8%,94.0%,and 69.8%for dibenzothiophene(DBT),4,6-dimethyldibenzothiophene(4,6-DMDBT),and benzothiophene(BT)in model oil,respectively.Notably,the DES maintains a desulfurization rate of 94.9%after five reuse cycles,demonstrating excellent recyclability.Through experimental data analysis,the reaction mechanism was further elucidated,revealing the synergistic mechanism of DES in both sulfide oxidation and extraction processes.
As a new type of surfactant for oil displacement,internal olefin sulfonates have attracted much attention in oil field in recent years.As tertiary oil recovery technology is applied to high-temperature and high-salt reservoirs,the problem of temperature resistance and salt resistance of surfactant emerges.The rotating drop method was adopted to investigate the effects of ionic strength of Na⁺ and Ca²⁺ on the oil-water interfacial tension reduction performance of two internal olefin sulfonates(A-18,I-20)with different degrees of branching.The experimental results show that the internal olefin sulfonates surfactants generally have good salt resistance.Hydrophobic alkyl branching can increase the interfacial activity of surfactants.The active fractions in crude oil can be mixed and adsorbed with surfactant molecules at the interface,which is an important factor governing the interfacial performance.The increase of ionic strength can weaken the electrostatic repulsion among surfactant molecules and increase the adsorption capacity of surfactants at the interface.Moreover,divalent calcium ions exhibit stronger molecular aggregation ability than monovalent sodium ions,further reducing the oil-water interfacial tension at high mass fraction.
Driven by the global energy transition and China's dual?carbon goals, clean and efficient utilization of carbonaceous energy has emerged as a core research hotspot in the energy field. Chemical looping gasification (CLG) technology, characterized by low carbon capture cost, high energy conversion efficiency and minimal pollutant emissions, offers a promising route for converting carbonaceous fuels into high?value syngas. This paper focuses on the application of chemical looping technology in syngas production from carbon?containing energy sources. It reviews the research progress in this field, compares it with conventional gasification processes, and summarizes the reaction mechanisms of chemical looping gasification and oxygen carriers. Compared with conventional processes, the unique advantages of syngas production by chemical looping technology are analyzed: the carbon conversion rate of coal chemical looping gasification is as high as 83.79%; the H2/CO volume ratio of petroleum coke chemical looping gasification is approximately 5 times that of conventional gasification, and it can also achieve CO2 capture; biomass chemical looping gasification can be realized at a relatively low temperature and can produce pure H2 without gas separation.
The activity of PtSn/Al2O3 catalyst has a significant impact on the activity and stability of propane dehydrogenation catalysts. To address the issues of easy migration and agglomeration of the active component Pt, which make it difficult to maintain high dispersion, the active phase of the catalyst was regulated by changing the precursor of the active component Pt, and its effect on the propane dehydrogenation performance was investigated. Characterization and analysis of the active phase and carbon deposition resistance of the catalyst were carried out using TEM, H2?TPR, TG, and Raman techniques. The results showed that under conditions with similar propane conversion rates, the selectivity of propylene increased from 86.96% to 93.92%, while the production of by?product methane significantly decreased. The catalyst prepared using octaethylporphyrin platinum as the precursor had a smaller active phase size and better dispersion. Using octaethylporphyrin platinum as the precursor can enhance the interaction between Pt and the support, significantly improve the stability of the active phase, effectively improve the catalyst's resistance to coking, and significantly reduce the amount of carbon deposition.
Metal diaphragms serve as key functional materials widely used in aerospace,microelectronics,chemical engineering,and other fields.As the core sensitive element in diaphragm pressure-reducing valves,their mechanical properties directly determine the valve's pressure regulating precision,stability,and service life.This paper systematically investigates the influence of key geometric parameters of the diaphragm and material properties on its mechanical performance under typical operating conditions.A mathematical model was established to analyze force distribution at the equilibrium position,where loads and constraints were applied,followed by the application of loads and constraints were applied,and the relationship between load and deflection was verified using the large deflection theory of corrugated diaphragms.A precise 3D parametric model of the diaphragm was built using SolidWorks software.The study employed the Finite Element Analysis(FEA)method,utilizing ANSYS software to conduct static structural simulation analysis on the diaphragm's geometric structure,parameters(width,height,thickness),and material properties.The results show that:the geometric structure of large arc corrugations is superior to sinusoidal corrugations;increasing the width of the outer corrugations increases the deformation,stress,and strain of the diaphragm,thus enhancing its sensitivity;increasing the corrugation height causes the diaphragm's elastic characteristics to first decrease and then increase;smaller diaphragm thickness results in better elastic characteristics;the elastic modulus of the diaphragm material is the dominant factor affecting its stiffness and deformation response-higher elastic modulus reduces deformation but increases stress,while materials with lower elastic modulus exhibit the opposite effect.Material selection requires balancing sensitivity,strength,and service life requirements.This research reveals the influence of the diaphragm's geometric structure,parameters,and material properties on its mechanical performance,providing an important theoretical basis and design guidance for the structural optimization design and high-performance material selection of diaphragms in diaphragm pressure-reducing valves.
Aiming to achieve noise isolation and vibration damping in engineering applications with simple and aesthetic structures,this paper designs a novel four-oscillator chiral phononic crystal.By incorporating helical scatterer branches as oscillators,the design breaks the inherent symmetry of conventional phononic crystals.Finite element simulation is first used to analyze the bandgap of the unit cell,followed by validation of the infinite periodic bandgap range through finite periodic arrangement.Further investigation into the effects of scatterer material parameters and the number of oscillators on the bandgap characteristics was conducted through parametric analysis.The results indicate that the chiral phononic crystal structure exhibits a total band gap widths of up to 642.12 Hz below 1 000 Hz,demonstrating excellent performance in low frequency noise isolation.
The regulation of metal cations in zeolites via ion exchange to enhance CO2 adsorption performance holds significant potential for the efficient industrial capture of CO2.To investigate the correlation between metal cation exchange time and CO2 adsorption performance of zeolites,four adsorbent samples(e.g.Ca-LTA-30)were prepared with exchange time as the independent variable.The textural properties,thermal stability,CO2 temperature-programmed desorption(CO2-TPD),and CO2 adsorption performance of these samples were characterized.Furthermore,the IAST(Ideal Adsorbed Solution Theory)selectivity of these samples for CO2/N2 gas mixtures with different volume ratios(20:80,50:50,80:20)was compared.The results indicate that the CO2 adsorption performance of LTA can be increased from 5.02 mmol/g to 6.05 mmol/g,while the SCO2/N2 can be improved from 59.7 to 118.5.In addition,through comparing the fitting performance of four adsorption models on the adsorption isotherms of CO2 and N2 on LTA and Ca-LTA series samples,it is found that the Langmuir-Freundlich model exhibits the best consistency with the experimental data and can effectively evaluate the CO2 adsorption behavior of the Ca-LTA series samples.
This paper proposes a distributed coordinated optimization method for multi-microgrid systems based on the Alternating Direction Method of Multipliers(ADMM).The proposed model comprehensively accounts for generation costs,energy storage operation,and inter-microgrid interactions,while employing second-order cone relaxation techniques to address nonlinear power flow constraints.By optimizing the ADMM iteration process and parameter selection,the method significantly improves computational efficiency while protecting data privacy through its distributed architecture.Case studies demonstrate that the method converges within only five iterations,achieves a 76.7%improvement in computational efficiency compared with centralized optimization,and maintains a solution accuracy within a 0.34%deviation from the global optimum.Compared to linear programming methods,the ADMM enhances voltage regulation performance by 40.0%and reduces line losses by 15.5%.The method exhibits excellent scalability with computational complexity increasing linearly with the number of microgrids,is applicable to various network topologies,and requires sharing only boundary interaction information,thus providing effective technical support for multi-microgrid coordination optimization.
In transformer fault diagnosis accuracy,addressing the limitations of traditional neural networks such as insufficient interpretability and weak temporal feature extraction capabilities,this study proposes a novel diagnostic model,LKAN which integrates Long Short-Term Memory(LSTM)with Kolmogorov-Arnold Network(KAN).The model first employs LSTM to model time-series data from transformer operations,extracting hidden states as temporal features.These features are then fed into the KAN layer,where B-spline functions enable nonlinear mapping and function decomposition,thereby enhancing both the model's expressiveness and interpretability.Experimental results on real-world power transformer datasets demonstrate that the LKAN model achieves a diagnostic accuracy of 98.80%,outperforming LSTM,Convolutional Neural Network(CNN),Gated Recurrent Unit(GRU),and single KAN models.Meanwhile,it exhibits strong generalization ability and stability.The LKAN model effectively integrates the temporal modeling capability of LSTM and the interpretability advantage of KAN.It provides a technical path with high accuracy and strong interpretability for intelligent fault diagnosis of transformers,and has good engineering promotion value.
This study investigates the microscopic properties of water-in-oil(W/O)emulsions,focusing on their stability and the formation patterns of liquid holdup.Through emulsification experiments and microscopic observation,the effects of water content,shear rate,and carbon dioxide(CO2)treatment on emulsion droplet size distribution and stability were systematically studied.Based on experimental data,a liquid holdup rate model was developed for the MH oil sample.The results indicate that the shear rate significantly affects the droplet size distribution and emulsion stability.A moderate shear rate(6 000～9 600 s-1)promotes emulsion stability and yields a uniform droplet distribution.When water content is below 30%,increasing the water content reduces the droplet size;however,high water content can show phase separation.CO2 saturation treatment can reduce interfacial tension and improve emulsion stability,but excessive CO2 release may destabilize the oil-water interface and promote droplet coalescence.Rational control of shear rate,water content,and CO2 concentration can effectively optimize pipeline transportation performance,reduce bottom liquid accumulation,and enhance the operational stability of the oilfield gathering and transportation system.This study provides theoretical support for the control of liquid holdup in CO2-driven gathering pipelines and holds significant engineering application value for oilfield production management.
ZnCu-BDC,a new MOFs material,was successfully synthesized by solvothermal method,with copper acetate and zinc nitrate as the metal centers and terephthalic acid(BDC)as the organic ligand.The structure,morphology,specific surface area and thermal stability of the materials were systematically characterized by scanning electron microscopy,X-ray polycrystalline powder diffraction,Fourier transform infrared spectroscopy,nitrogen adsorption and thermogravimetric-differential thermal analyzer.The catalytic performance of ZnCu-BDC in naphthalene-containing simulated oil was investigated by using naphthalene as the aromatic hydrocarbon model compound in simulated oil.The results show that the ZnCu-BDC material has the same particle size,smooth surface,good thermal stability,complete decomposition at 450℃,a large number of micropores,and a nitrogen adsorption-desorption curve with the characteristics of H3 curve.Under the optimal conditions obtained after the investigation(n(Cu)/n(Zn)is 1.0∶2.0,reaction time 6 h,reaction temperature 70℃,pH=5),the removal efficiency of ZnCu-BDC material for aromatic hydrocarbon model compounds in simulated oil can reach 91%.
The heterogeneity of the Tahe fractured-vuggy reservoir is strong,and the fluid flow state is complex.The flow and waterflooding mechanisms of high-asphaltene heavy oil remain poorly understood,posing significant challenges to the effective implementation of water injection strategies.Based on a visualization model of fractured-vuggy reservoirs,experimental investigations were carried out on the flow and displacement behavior of heavy oil with different viscosities.The relationship between the flow resistance coefficient of asphaltene containing heavy oil and the viscosity and flow rate was established,and dynamic quantification of oil saturation in different vuggys was achieved through image recognition.The characteristics of waterflooding of high asphaltene heavy oil in fractured-vuggy reservoirs and the influence mechanisms of heavy oil viscosity,fractures,and water injection rate were clarified.The results indicate that the viscosity of heavy oil increased from 59 mPa·s(medium viscosity)to 1 090 mPa·s(extra viscosity),the apparent threshold pressure gradient of heavy oil in the fracture cavity increased by one order of magnitude,the flow resistance coefficient increased by three times,and the waterflooding recovery rate decreased by 9.6 percentage points.Increased heavy oil viscosity also reduced the number of vugs affected by waterflooding,thereby increasing the remaining oil volume in attic configurations,localized high points,and along cavity walls.The scale,length,and spatial distribution of crack width have a greater impact on the flow direction of waterflooding heavy oil,and are stronger than the gravity differentiation of oil and water.Appropriately increasing the water injection rate enhances the ability of water flooding to spread and break through small-scale fractures.
