An Elastoplastic Fracture Model Based on Bond-Based Peridynamics

Fracture in ductile materials often occurs in conjunction with plastic deformation.However,in the bond-based peridynamic(BB-PD)theory,the classic mechanical stress is not defined inherently.This makes it difficult to describe plasticity directly using the classical plastic theory.To address the above issue,a unified bond-based peridynamics model was proposed as an effective tool to solve elastoplastic fracture problems.Compared to the existing models,the proposed model directly describes the elastoplastic theory at the bond level without the need for additional calculation means.The results obtained in the context of this model are shown to be consistent with FEM results in regard to force-displacement curves,displacement fields,stress fields,and plastic deformation regions.The model exhibits good capability of capturing crack propagation in ductile material failure problems.

Delivery of luminescent particles to plants for information encoding and storage

In the era of smart agriculture,the precise labeling and recording of growth information in plants pose challenges for modern agricultural production.This study introduces strontium aluminate particles coated with H_(3)PO_(4)as luminescent labels capable of spatial embedding within plants for information encoding and storage during growth.The encapsulation with H_(3)PO_(4)imparts stability and enhanced luminescence to SrAl_(2)O_(4):Eu^(2+),Dy^(3+)(SAO).Using SAO@H_(3)PO_(4)as a low-damage luminescent label,we implement its delivery into plants through microneedles(MNs)patches.The embedded SAO@H_(3)PO_(4)within plants exhibits sustained and unaltered high signal-to-noise afterglow emission,with luminous intensity remaining at approximately 78%of the original for 27 days.To cater to diverse information recording needs,MNs of various geometric shapes are designed for loading SAO@H3PO4,and the luminescent signals in different shapes can be accurately identified through a designed program,the corresponding information can be conveniently viewed on a computer.Additionally,inspired by binary information concepts,MNs patches with specific arrangements of luminescent and non-luminescent points are created,resulting in varied luminescent MNs arrays on leaves.An advanced camera system with a tailored program accurately identifies and maps the labels to the corresponding recorded information.These findings showcase the potential of low-damage luminescent labels within plants,paving the way for convenient and widespread storage of plant growth information.

Self-Compassion Moderates the Effect of Contingent Self-Esteem on Well-Being:Evidence from Cross-Sectional Survey and Experiment

Contingent self-esteem captures the fragile nature of self-esteem and is often regarded as suboptimal to psychological functioning.Self-compassion is another important self-related concept assumed to promote mental health and well-being.However,research on the relation of self-compassion to contingent self-esteem is lacking.Two studies were conducted to explore the role of selfcompassion,either as a personal characteristic or an induced mindset,in influencing the effects of contingent self-esteem on well-being.Study 1 recruited 256 Chinese college students(30.4%male,mean age=21.72 years)who filled out measures of contingent self-esteem,self-compassion,and well-being.The results found that self-compassion moderated the effect of contingent self-esteem on well-being.In Study 2,a sample of 90 Chinese college students(34%male,mean age=18.39 years)were randomly assigned to either a control or self-compassion group.They completed baseline trait measures of contingent self-esteem,self-compassion,and self-esteem.Then,they were led to have a 12-min break(control group)or listen to a 12-min self-compassion audio(self-compassion group),followed by a social stress task and outcome measures.The results demonstrated the effectiveness of the brief self-compassion training and its moderating role in influencing the effects of contingent self-esteem on negative affects after the social stress task.This research provides implications that to equip with a self-compassionate mindset could lower the risk of the impairment of well-being associated with elements of contingent selfesteem,which involves a fragile sense of self-worth.It may also provide insights into the development of an“optimal selfesteem”and the improvement of well-being.

胃神经内分泌癌的临床病理特征及预后分析

目的:探讨胃神经内分泌癌(gastric neuroendocrine carcinoma,G-NEC)、胃混合性腺-神经内分泌癌(gastric mixed adenoendocrine carcinoma,G-MANEC)的临床病理特征及预后因素。方法:回顾性收集2015年5月至2023年5月于长治医学院附属和平医院就诊并行手术治疗的67例G-NEC、G-MANEC患者的临床资料,并分析其病理特征。结果:与胃腺癌相比,G-NEC、GMANEC患者好发于男性的贲门部、确诊时年龄更大、肿瘤直径更大、术前更易发生贫血、低白蛋白、更易侵犯神经和脉管、肿瘤浸润深度更深、淋巴结转移数更多、TNM分期更晚、术后更易发生远处转移。G-NEC、G-MANEC患者的预后较胃腺癌差(P=0.001),而G-NEC和G-MANEC在病理特征(P>0.05)及预后分析(P=0.212)差异均无统计学意义。单因素生存分析显示:年龄、术前白蛋白、术前CEA、淋巴结转移数、TNM分期和术后远处转移是影响患者总生存期(overall survival,OS)的危险因素;多因素分析显示:年龄、术前白蛋白、TNM分期和术后远处转移是影响OS的独立危险因素。结论:G-NEC、G-MANEC与胃腺癌的临床特征存在显著性差异,且确诊时多处于进展期,术后易发生远处转移。年龄>60岁、术前白蛋白<40 g/L、TNM分期Ⅱ/Ⅲ期、术后发生远处转移的患者预后较差。

Microscopic mechanism study and process optimization of dimethyl carbonate production coupled biomass chemical looping gasification system

Biomass chemical looping gasification technology is one of the essential ways to utilize abundant biomass resources.At the same time,dimethyl carbonate can replace phosgene as an environmentfriendly organic material for the synthesis of polycarbonate.In this paper,a novel system coupling biomass chemical looping gasification with dimethyl carbonate synthesis with methanol as an intermediate is designed through microscopic mechanism analysis and process optimization.Firstly,reactive force field molecular dynamics simulation is performed to explore the reaction mechanism of biomass chemical looping gasification to determine the optimal gasification temperature range.Secondly,steady-state simulations of the process based on molecular dynamics simulation results are carried out to investigate the effects of temperature,steam to biomass ratio,and oxygen carrier to biomass ratio on the syngas yield and compositions.In addition,the main energy indicators of biomass chemical looping gasification process including lower heating value and cold gas efficiency are analyzed based on the above optimum parameters.Then,two synthesis stages are simulated and optimized with the following results obtained:the optimal temperature and pressure of methanol synthesis stage are 150℃ and 4 MPa;the optimal temperature and pressure of dimethyl carbonate synthesis stage are 140℃ and 0.3 MPa.Finally,the pre-separation-extraction-decantation process separates the mixture of dimethyl carbonate and methanol generated in the synthesis stage with 99.11%purity of dimethyl carbonate.Above results verify the feasibility of producing dimethyl carbonate from the perspective of multi-scale simulation and realize the multi-level utilization of biomass resources.

Fast GNSS Acquisition Algorithm Based on SFFT with High Noise Immunity

The Global Navigation Satellite System(GNSS)has been widely used in various fields.To achieve positioning,the receiver must first lock the satellite signal.This is a complicated and expensive process that consumes a lot of resources of the receiver.For this reason,this paper proposes a new fast acquisition algorithm with High Signal-tonoise ratio(SNR)performance based on sparse fast Fourier transform(HSFFT).The algorithm first replaces the IFFT process of the traditional parallel code phase capture algorithm with inverse sparse fast Fourier transform(ISFFT)with better computing performance,and then uses linear search combined with code phase discrimination to replace the positioning loop and the estimation loop with poor noise immunity in ISFFT.Theoretical analysis and simulation results show that,compared with the existing SFFT parallel code phase capture algorithm,the calculation amount of this algorithm is reduced by 19%,and the SNR performance is improved by about 5dB.Compared with the classic FFT parallel code phase capture algorithm,the calculation amount of the algorithm in this paper is reduced by 43%,and when the capture probability is greater than 95%,the SNR performance of the two is approximately the same.

Atmospheric pressure pulsed modulated arc discharge plasma

Direct-current(DC)arc plasma has great application values in the field of the chemical industry,but it has the problem of low energy efficiency.Facing the requirement for improving the energy efficiency of the arc,this paper proposes a unique method of pulsed modulated arc(PMA).This method uses high-frequency pulses and reduces the arc current to improve the control of electron temperature.The electrical characteristics,optical characteristics and products are tested.The test results show that during the PMA process,all of the experimental results which include voltage,current and light will significantly increase.These results are analyzed from the perspective of functionality,repeatability and energy conversion.The analysis results show that although the PMA method does not show good parameter consistency,it has potential application prospects because it increases the energy conversion rate by 4.5%and 8%from the perspective of light and products,respectively.

Repurposing EV Batteries for Storing Solar Energy

1.Introduction Carbon neutrality has emerged as a global goal due to its pivotal role in addressing the challenges of global climate change.Before the United Nations Climate Summit was held in November 2020,124 countries promised to reach net-zero emissions[1].Solar energy is one of the important renewable energy sources that significantly curtail carbon emissions originating from fossil fuels.

The Advantages and Disadvantages of Skin Staple Suture Compared with Traditional Suture in Brain Surgery in Primary Hospital:A Randomized Controlled Study

Objective:This paper aims to compare the effect of skin staple suture and traditional silk suture in scalp suture surgery.Methods:A total of 80 craniocerebral surgery patients were included in this study,and the patients were randomly divided into observation group and control group,with 40 cases in each group.The observation group used disposable skin stapler to suture the scalp incision,and the control group used conventional silk suture to suture the incision.Statistical analysis was carried out on 6 indicators including suturing speed,healing under-scab,incision necrosis,incision cerebrospinal fluid(CSF)leakage,incision infection,and postoperative“centipede-shaped”scar incidence rate of the two suture methods.Results:There was no significant difference between the groups in terms of postoperative healing under-scab,incision necrosis,incision CSF leakage,and intracranial infection(P>0.05).The suturing speed in the observation group was 15.2±0.7 cm/min,which was significantly faster than 7.4±0.3 cm/min in the control group(P<0.05).The incidence of“centipede-shaped”scars in the observation group was significantly lower than that in the control group at 1 to 6 months after operation(P<0.05).Conclusion:Compared with traditional silk suture,skin staple suture has obvious advantages in suture speed and cosmetic effect.

A two-stage optimization method for unmanned aerial vehicle inspection of an oil and gas pipeline network

Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and downstream.To improve the reliability and safety of the oil and gas pipeline network, inspections are implemented to minimize the risk of leakage, spill and theft, as well as documenting actual incidents. In recent years, unmanned aerial vehicles have been recognized as a promising option for inspection due to their high efficiency. However, the integrated optimization of unmanned aerial vehicle inspection for oil and gas pipeline networks, including physical feasibility, the performance of mission, cooperation, real-time implementation and three-dimensional(3-D) space, is a strategic problem due to its large-scale,complexity as well as the need for efficiency. In this work, a novel mixed-integer nonlinear programming model is proposed that takes into account the constraints of the mission scenario and the safety performance of unmanned aerial vehicles. To minimize the total length of the inspection path, the model is solved by a two-stage solution method. Finally, a virtual pipeline network and a practical pipeline network are set as two examples to demonstrate the performance of the optimization schemes. Moreover, compared with the traditional genetic algorithm and simulated annealing algorithm, the self-adaptive genetic simulated annealing algorithm proposed in this paper provides strong stability.

A metaheuristic method for the multireturn-to-depot petrol truck routing problem with time windows

The petrol truck routing problem is an important part of the petrol supply chain.This study focuses on determining routes for distributing petrol products from a depot to petrol stations with the objective of minimizing the total travel cost and the fixed cost required to use the trucks.We propose a mathematical model that considers petrol trucks returning to a depot multiple times and develop a heuristic algorithm based on a local branch-and-bound search with a tabu list and the Metropolis acceptance criterion.In addition,an approach that accelerates the solution process by adding several valid inequalities is presented.In this study,the trucks are homogeneous and have two compartments,and each truck can execute at most three tasks daily.The sales company arranges the transfer amount and the time windows for each station.The performance of the proposed algorithm is evaluated by comparing its results with the optimal results.In addition,a real-world case of routing petrol trucks in Beijing is studied to demonstrate the effectiveness of the proposed approach.

Study on preparation of fast curing novolaks for the shell process

To save energy and raise molding and coremaking productivity, the synthetic procedure of novolaks for the shell process was investigated. The study indicated that it was difficult to obtain fast curing novolaks under strongly acidic conditions alone. A novel synthetic procedure was proposed for preparing novolaks in a two-step manner, a divalent metal salt catalyzed novolak preparation followed by a strong acid catalyzed novolak preparation. The optimum conditions for the two-step procedure were determined by orthogonal experiment design. The results showed that it was easy to prepare fast curing novolaks with cure time in the range of 20 s to 30 s and softening point in the range of 80℃ to 90℃ under complex catalysis conditions.

Investigation on the Relationship between Population Density and Satellite Image Features——a Deep Learning Based Approach

Timely and accurate population statistic data plays an important role in many fields.To illustrate the demographic characteristics,population density is a crucial factor in evaluating population data.With a dynamic regional migration in population,it is a challenging job to evaluate population density without a census-based survey.We present the approach to classify satellite images in different magnitudes in population density and execute the comparative experiment to discuss the factors that influence the identification to the images with the deep learning approach.In this paper,we use satellite imagery and community population density data.With convolutional neural networks,we evaluated the performance of CNN on population estimation with satellite images,found the features that are important in population estimation,and then perform the sensitive analysis.

Construction of N-doped carbon frames anchored with Co single atoms and Co nanoparticles as robust electrocatalyst for hydrogen evolution in the entire pH range

The development of low-cost, efficient, and high atomic economy electrocatalysts for hydrogen evolution reaction(HER) in the entire p H range for sustainable hydrogen production is of great importance but still challenging. Herein, we synthesize a highly dispersed N-doped carbon frames(NCFs) anchored with Co single atoms(SAs) and Co nanoparticles(NPs) catalyst by a doping-adsorption-pyrolysis strategy for electrocatalytic hydrogen evolution. The Co SAs-Co NPs/NCFs catalyst exhibits an excellent HER activity with small overpotential, low Tafel slope, high turnover frequency as well as remarkable stability. It also exhibits a superior HER performance in the entire p H range. Combining with experimental and theoretical calculation, we find that Co SAs with Co-N_(3) coordination structure and Co NPs have a strong interaction for promoting synergistic HER electrocatalytic process. The H_(2)O molecule is easily activated and dissociated on Co NPs, while the generated H^(*) is easily adsorbed on Co SAs for HER, which makes the Co SAs-Co NPs/NCFs catalyst exhibit more suitable H adsorption strength and more conducive to the activation and dissociation of H_(2)O molecules. This work not only proposes a novel idea for constructing coupling catalyst with atomic-level precision, but also provides strong reference for the development of high-efficiency HER electrocatalysts for practical application.

Mechanism analysis and simulation of methyl methacrylate production coupled chemical looping gasification system

Nowadays,the efficient and cleaner utilization of coal have attracted wide attention due to the rich coal and rare oil/gas resources structure in China.Coal chemical looping gasification(CCLG)is a promising coal utilization technology to achieve energy conservation and emission reduction targets for highly pure synthesis gas.As a downstream product of synthesis gas,methyl methacrylate(MMA),is widely used as raw material for synthesizing polymethyl methacrylate and resin products with excellent properties.So this paper proposes a novel system integrating MMA production and CCLG(CCLG-MMA)processes aiming at"energy saving and low emission",in which the synthesis gas produced by CCLG and purified by dry methane reforming(DMR)reaction and Rectisol process reacts with ethylene for synthesizing MMA.Firstly,the reaction mechanism of CCLG is investigated by using Reactive force field(ReaxFF)MD simulation based on atomic models of char and oxygen carrier(Fe_(2)O_(3))for obtaining optimum reaction temperature of fuel reactor(FR).Secondly,the steady-state simulation of CCLG-MMA system is carried out to verify the feasibility of MMA production.The amount of CO_(2)emitted by CCLG process and DMR reaction is 0.0028(kg CO_(2))^(-1)·(kg MMA)^(-1).The total energy consumption of the CCLG-MMA system is 45521 kJ·(kg MMA)^(-1),among which the consumption of MMA production part is 25293 k(·kg MMA)^(-1).The results show that the CCLG-MMA system meets CO_(2)emission standard and has lower energy consumption compared to conventional MMA production process.Finally,one control scheme is designed to verify the stability of CCLG-MMA system.The CCLG-MMA integration strategy aims to obtain highly pure MMA from multi-scale simulation perspectives,so this is an optimal design regarding all factors influencing cleaner MMA production.

An Ui Design Optimization Strategy for General App in Big Data Environment

Due to the huge amount of increasing data, the requirements of people forelectronic products such as mobile phones, tablets, and notebooks are constantlyimproving. The development and design of various software applications attach greatimportance to users’ experiences. The rationalized UI design should allow a user not onlyenjoy the visual design experience of the new product but also operating it morepleasingly. This process is to enhance the attractiveness and performance of the newproduct and thus to promote the active usage and consuming conduct of users. In thispaper, an UI design optimization strategy for general APP in the big data environment isproposed to get better user experience while effectively obtaining information. Anexperimental example of a library APP is designed to optimize the user experience. Theexperimental results show that the user-centered UI design is the core of optimization,and user portrait based on big data platforms is the key to UI design.

Polarized red, green, and blue light emitting diodes fabricated with identical device configuration using rubbed PEDOT:PSS as alignment layer

Polarized red, green, and blue light emitting diodes(LEDs) are successfully fabricated using polyfluorene and its derivatives, namely, poly(9,9-dioctylfluorene)(PFO), poly(9,9-dioctylfluorene-co-benzothiadiazole)(F8BT),and poly(triphenylamine-co-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole-co-benzo[c]thiadiazole-co-9,9-dioctyl-9 Hfluorene)(Red F).Rubbed hole transport layer poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate)(PEDOT:PSS)is employed in the devices as the alignment layer to achieve fully monodomain alignment in all polymer layers.Red F is blended with F8BT to realize the polarized electroluminescence of red light(dichroic ratio ~3.3), despite having no liquid crystallinity itself.Comparing PFO/F8BT blend to F8BT, higher efficiency of polarized emission is found due to the energy transfer.All the polarized LEDs exhibit pronounced dichroism and efficient polarized emission compared to the non-alignment regular devices.

Implementation of OpenMP Parallelization of Rate-Dependent Ceramic Peridynamic Model

A rate-dependent peridynamic ceramic model,considering the brittle tensile response,compressive plastic softening and strain-rate dependence,can accurately represent the dynamic response and crack propagation of ceramic materials.However,it also considers the strain-rate dependence and damage accumulation caused by compressive plastic softening during the compression stage,requiring more computational resources for the bond force evaluation and damage evolution.Herein,the OpenMP parallel optimization of the rate-dependent peridynamic ceramicmodel is investigated.Also,themodules that compute the interactions betweenmaterial points and update damage index are vectorized and parallelized.Moreover,the numerical examples are carried out to simulate the dynamic response and fracture of the ceramic plate under normal impact.Furthermore,the speed-up ratio and computational efficiency by multi-threads are evaluated and discussed to demonstrate the reliability of parallelized programs.The results reveal that the totalwall clock time has been significantly reduced after optimization,showing the promise of parallelization process in terms of accuracy and stability.

Comprehensive zoning of biomass energy heating in EU countries reference for China from European experience

Heat is the largest energy end-use in the world,accounting for about 50%of global final energy consumption.In 2019,the International Energy Agency pointed out that the development of renewable energy heating has become a key way for the global response to climate change,environmental pollution control,energy transformation and sustainable development.Biomass energy as a priority for the development of renewable heat sources has been valued by countries around the world.Developed earlier in the EU countries,their biomass heating technology is more mature,and their policy system is more comprehensive.Accounting for 86%of the total renewable thermal energy consumption,biothermal energy in these countries has achieved significant effect and become an important driving force for the decarbonization of the heating industry.This practice has a very high demonstration effect globally.This paper constructs a comprehensive zoning theoretical framework of biomass energy heating and utilization in the EU countries.Based on the calculation of the supply and demand potential of biomass energy heating system,the FCM method is used to quantify the status of biomass resource utilization in 28 EU countries.The results show that there are significant differences in the utilization of biomass energy heating in the EU countries,which can be divided into five categories of comprehensive zones,which are the key development category(Finland,Sweden,Denmark,Estonia,Lithuania and Latvia),resource priority category(Austria,Croatia,Bulgaria,Romania,and Slovenia),policy-oriented category(Germany,Italy,Portugal,and Cyprus),good-potential category(Czech Republic,Hungary,Greece,Spain,Poland,France,and Slovakia)and under-developed category(UK,Netherlands,Belgium,Ireland,Luxembourg and Malta).At the same time,this paper discusses the characteristics and causes of biomass heating utilization of different types of EU countries,and summarizes the mature heating systems and rich experience in the EU countries with China’s current heating situation and its future challenges concerning renewable energy development.Finally,this study provides some implications for China’s clean heating development,energy efficient use,energy supply security and energy structure upgrade.

Inner peace makes you live longer

The question of how we live longer-and why only a minority of humans have good health and a long life-has confused people for millennia.Over the past few decades,we have learned that human lifespan is determined by both the genes and external influences,and that these factors act,by means of numerous genetic pathways,to regulate the cellular and systemic processes that ultimately cause aging and death.