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Microstructure and wear characteristics of ATZ ceramic particle reinforced gray iron matrix surface composites

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China Foundry 2018年第3期15卷 167-172页

作者： Xue Ma liang-feng li Fan Zhang Zu-hua Zhang Hao Wang En-ze Wang School of Materials Science and Engineering Southwest University of Science and Technology Chengdu Aerospace Superalloy Technology Co. Ltd Centre for Future Materials University of Southern Queensland

The alumina toughened zirconia(ATZ) ceramic particle reinforced gray iron matrix surface composite was successfully manufactured by pressureless infi ltration. The porous preform played a key role in the infi ltrating progress. The microstructure was observed by scanning electron microscopy(SEM); the phase constitutions was analyzed by X-ray diffraction(XRD); and the hardness and wear resistance of selected specimens were tested by hardness testing machine and abrasion testing machine, respectively. The addition of high carbon ferrochromium powders leads to the formation of white iron during solidifi cation. The wear volume loss rates of ATZ ceramic particle reinforced gray iron matrix surface composite decreases fi rst, and then tends to be stable. The wear resistance of the composite is 2.7 times higher than that of gray iron matrix. The reason is a combination of the surface hardness increase of gray iron matrix and ATZ ceramic particles and alloy carbides protecting effect on gray iron matrix.

关键词： metal-matrix surface composites pressureless infiltrating particle-reinforcement surface alloying wear testing

Pd cluster decorated free standing flexible cathode for high performance li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： liang Guo Guoliang Zhang Ruonan Yang Dongmei Zhang Xiuqi Zhang Han Yu Xia li feng Dang Key Laboratory for liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical application.Exploring highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance LOBs.Herein,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ratio.Meanwhile,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for li species reduces the initial dynamical energy barrier during discharging process.The current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming liang Guangning li Min Xu Junmin Zhao feng Hao Hongbo Shi Northwestern Polytechnical University School of Astronautics Xi’an 710072China China North Industries Group Corporation No 203 Research Institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is proposed.The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application prospect.Firstly,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is constructed.In order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried out.The simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight simulation.Secondly,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy respectively.The intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight parameters.Compared with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability error.The intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid

Whole-genome sequencing in medicinal plants:current progress and prospect

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Science China(life Sciences) 2024年第2期67卷 258-273页

作者： Yifei Pei liang Leng Wei Sun Baocai liu Xue feng Xiwen li Shilin Chen Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700China Institute of Herbgenomics Chengdu University of Traditional Chinese MedicineChengdu 611137China Innovative Institute of Chinese Medicine and Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137China Institute of Agricultural Bioresource Fujian Academy of Agricultural SciencesFuzhou 350003China

Advancements in genomics have dramatically accelerated the research on medicinal plants,and the development of herbgenomics has promoted the“Project of 1K Medicinal Plant Genome”to decipher their genetic code.However,it is difficult to obtain their high-quality whole genomes because of the prevalence of polyploidy and/or high genomic heterozygosity.Whole genomes of 123 medicinal plants were published until September 2022.These published genome sequences were investigated in this review,covering their classification,research teams,ploidy,medicinal functions,and sequencing strategies.More than 1,000 institutes or universities around the world and 50 countries are conducting research on medicinal plant genomes.Diploid species account for a majority of sequenced medicinal plants.The whole genomes of plants in the Poaceae family are the most studied.Almost 40%of the published papers studied species with tonifying,replenishing,and heat-cleaning medicinal effects.Medicinal plants are still in the process of domestication as compared with crops,thereby resulting in unclear genetic backgrounds and the lack of pure lines,thus making their genomes more difficult to complete.In addition,there is still no clear routine framework for a medicinal plant to obtain a high-quality whole genome.Herein,a clear and complete strategy has been originally proposed for creating a high-quality whole genome of medicinal plants.Moreover,whole genome-based biological studies of medicinal plants,including breeding and biosynthesis,were reviewed.We also advocate that a research platform of model medicinal plants should be established to promote the genomics research of medicinal plants.

关键词： herbgenomics whole genome high throughput sequencing research strategy model species application

Multimorbidity and mortality among older patients with coronary heart disease in Shenzhen,China

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Journal of Geriatric Cardiology 2024年第1期21卷 81-89页

作者： Fu-Rong li Shuang WANG Xia li Zhi-Yuan CHENG Cheng JIN Chun-Bao MO Jing ZHENG feng-Chao liang Dong-feng GU Shenzhen Key Laboratory of Cardiovascular Health and Precision Medicine Southern University of Science and TechnologyShenzhenGuangdongChina School of Public Health and Emergency Management Southern University of Science and TechnologyShenzhenGuangdongChina Shenzhen Health Development Research and Data Management Center ShenzhenChina School of Medicine Southern University of Science and TechnologyShenzhenGuangdongChina

BACKGROUND The current understanding of the magnitude and consequences of multimorbidity in Chinese older adults with coronary heart disease(CHD)is insufficient.We aimed to assess the association and population-attributable fractions(PAFs)between multimorbidity and mortality among hospitalized older patients who were diagnosed with CHD in Shenzhen,China.METHODS We conducted a retrospective cohort study of older Chinese patients(aged≥65 years)who were diagnosed with CHD.Cox proportional hazards models were used to estimate the associations between multimorbidity and all-cause and cardiovascular disease(CVD)mortality.We also calculated the PAFs.RESULTS The study comprised 76,455 older hospitalized patients who were diagnosed with CHD between January 1,2016,and August 31,2022.Among them,70,217(91.9%)had multimorbidity,defined as the presence of at least one of the predefined 14 chronic conditions.Those with cancer,hemorrhagic stroke and chronic liver disease had the worst overall death risk,with adjusted HRs(95%CIs)of 4.05(3.77,4.38),2.22(1.94,2.53),and 1.85(1.63,2.11),respectively.For CVD mortality,the highest risk was observed for hemorrhagic stroke,ischemic stroke,and chronic kidney disease;the corresponding adjusted HRs(95%CIs)were 3.24(2.77,3.79),1.91(1.79,2.04),and 1.81(1.64,1.99),respectively.All-cause mortality was mostly attributable to cancer,heart failure and ischemic stroke,with PAFs of 11.8,10.2,and 9.1,respectively.As for CVD mortality,the leading PAFs were heart failure,ischemic stroke and diabetes;the corresponding PAFs were 18.0,15.7,and 6.1,respectively.CONCLUSIONS Multimorbidity was common and had a significant impact on mortality among older patients with CHD in Shenzhen,China.Cancer,heart failure,ischemic stroke and diabetes are the primary contributors to PAFs.Therefore,prioritizing improved treatment and management of these comorbidities is essential for the survival prognosis of CHD patients from a holistic public health perspective.

关键词： patients morbidity mortality

Progress in processing of porous titanium: a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-li Yang Xian-feng Du Zhi-lin Xu Zhong-Shuai liang li-Long Xiong Engineering Research Center of Energy Storage Materials and Devices Ministry of Education School of Chemistry Xi'an Jiaotong University

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace, marine engineering and biomedical fields due to their high corrosion resistance, low density, good biocompatibility and excellent mechanical properties. Therefore, in this paper, a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes) for fabricating porous titanium is firstly covered in terms of their working principles, capabilities, shortcomings and strengths. Simultaneously, the influencing factors of various methods on final pore structure of porous Ti are involved. Secondly, a summary of the chemical methods(CM) to obtain the porous Ti is also provided,such as dealloying method and reduction method. Finally,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Thoracic spine infection caused by Pseudomonas fluorescens:A case report and review of literature

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World Journal of Clinical Cases 2024年第12期12卷 2099-2108页

作者： liang li Bao-Hua Zhang Jin-feng Cao li-Jin Zhang ling-ling Guo Department of Traditional Chinese Medicine Zibo Central HospitalZibo 255000Shandong ProvinceChina Department of Pathology Zibo Central HospitalZibo 255000Shandong ProvinceChina Department of Medical Imaging Zibo Central HospitalZibo 255000Shandong ProvinceChina

BACKGROUND The clinical incidence of spinal infection is gradually increasing,and its onset is insidious,easily leading to missed diagnosis and misdiagnosis,which may lead to serious complications such as nervous system dysfunction,spinal instability and/or deformity,and cause a huge burden on society and families.Early identification of the causative agent and precision medicine will greatly reduce the suffering of patients.At present,the main pathogenic bacteria that cause spinal infection are Staphylococcus aureus,Streptococcus,Pneumococcus,Escherichia coli,and Klebsiella.There are no reports of spinal infection caused by Pseudomonas fluorescens.CASE SUMMARY We report a 32-year-old female patient with spinal infection.She presented with flank pain,initially thought to be bone metastases or bone tuberculosis,and had a family background of tumors.Her clinical features and changes in imaging and laboratory tests led to the suspicion of thoracic spine infection.Histopathology of the lesion showed inflammation,tissue culture of the lesion was negative several times,and the possible pathogen-Pseudomonas fluorescens was found after gene sequencing of the lesion.The patient recovered completely after a full course of antibiotic treatment.CONCLUSION This report increases the range of pathogens involved in spinal infections,highlights the unique advantages of gene sequencing technology in difficult-todiagnose diseases,and validates conservative treatment with a full course of antibiotics for spinal infections without complications.

关键词： Thoracic spine infection Pseudomonas fluorescens Spinal infection Case report

Data-driven Wasserstein distributionally robust chance-constrained optimization for crude oil scheduling under uncertainty

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Chinese Journal of Chemical Engineering 2024年第5期69卷 152-166页

作者： Xin Dai liang Zhao Renchu He Wenli Du Weimin Zhong Zhi li feng Qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Engineering Research Center of Process System Engineering Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil refining.But uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans made by the traditional deterministic optimization models infeasible.A data-driven Wasserstein distributionally robust chance-constrained(WDRCC)optimization approach is proposed in this paper to deal with demand uncertainty in crude oil scheduling.First,a new deterministic crude oil scheduling optimization model is developed as the basis of this approach.The Wasserstein distance is then used to build ambiguity sets from historical data to describe the possible realizations of probability distributions of uncertain demands.A cross-validation method is advanced to choose suitable radii for these ambiguity sets.The deterministic model is reformulated as a WDRCC optimization model for crude oil scheduling to guarantee the demand constraints hold with a desired high probability even in the worst situation in ambiguity sets.The proposed WDRCC model is transferred into an equivalent conditional value-at-risk representation and further derived as a mixed-integer nonlinear programming counterpart.Industrial case studies from a real-world refinery are conducted to show the effectiveness of the proposed method.Out-of-sample tests demonstrate that the solution of the WDRCC model is more robust than those of the deterministic model and the chance-constrained model.

关键词： Distributions Model Optimization Crude oil scheduling Wasserstein distance Distributionally robust chance constraints

Epidemiological Surveillance: Genetic Diversity of Rotavirus Group A in the Pearl River Delta, Guangdong, China in 2019

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Biomedical and Environmental Sciences 2024年第3期37卷 278-293页

作者： JIANG Jie Ying liang Dan WANG li XIAO Yun liang Yu feng KE Bi Xia SU Juan XIAO Hong WANG Tao ZOU Min li Hong Jian KE Chang Wen School of Public Health Shantou UniversityShantou 515063GuangdongChina Guangdong Provincial Center for Disease Control and Prevention Guangdong Workstation for Emerging Infectious Disease Control and PreventionGuangzhou 511430GuangdongChina Guangdong Provincial Key Laboratory of Virology Institute of Medical MicrobiologyJinan UniversityGuangzhou 510632GuangdongChina School of Public Health Sun Yat-sen UniversityGuangzhou 510275GuangdongChina School of Public Health Southern Medical UniversityGuangzhou 510515GuangdongChina Shantou University Medical College Shantou 515041GuangdongChina

Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China.Methods This study included individuals aged 28 days–85 years.A total of 706 stool samples from patients with acute gastroenteritis collected between January 2019 and January 2020 were analyzed for 17 causative pathogens,including RVA,using a Gastrointestinal Pathogen Panel,followed by genotyping,virus isolation,and complete sequencing to assess the genetic diversity of RVA.Results The overall RVA infection rate was 14.59%(103/706),with an irregular epidemiological pattern.The proportion of co-infection with RVA and other pathogens was 39.81%(41/103).Acute gastroenteritis is highly prevalent in young children aged 0–1 year,and RVA is the key pathogen circulating in patients 6–10 months of age with diarrhea.G9P[8](58.25%,60/103)was found to be the predominant genotype in the RVA strains,and the 41 RVA-positive strains that were successfully sequenced belonged to three different RVA genotypes in the phylogenetic analysis.Recombination analysis showed that gene reassortment events,selection pressure,codon usage bias,gene polymorphism,and post-translational modifications(PTMs)occurred in the G9P[8]and G3P[8]strains.Conclusion This study provides molecular evidence of RVA prevalence in the Pearl River Delta region of China,further enriching the existing information on its genetics and evolutionary characteristics and suggesting the emergence of genetic diversity.Strengthening the surveillance of genotypic changes and gene reassortment in RVA strains is essential for further research and a better understanding of strain variations for further vaccine development.

关键词： Infectious diarrheal disease Rotavirus Phylogenetic analysis Gene rearrangement Codon usage bias Genetic diversity