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Design study of charge-stripping scheme of heavy ion beams for HIAF-BRing

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Nuclear Science and Techniques 2024年第5期35卷 30-41页

作者： Jun-jie zhang Zhi-You Xu Jin-Quan zhang Wen-Wen Ge Liang-Ting Sun Huan-Yu Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Charge strippers play an essential role in heavy-ion accelerators by stripping the projectile ions to higher charge states to enhance the acceleration efficiency downstream of the stripper.In the high-energy mode of the booster ring(BRing)of the high-intensity heavy-ion accelerator facility,the pre-accelerated ions from the iLinac will be stripped by a carbon foil to higher charge states and then injected into the BRing.The key parameters of the stripper and stripped ions were calculated,and the influence of stripping on the beam quality was discussed.To get high stripping efficiencies,the foil thicknesses and resultant charge state distributions for the typical ions were determined by the code ETACHA.The equilibrium thickness was obtained for the U beam,while the stripper thicknesses for the Xe and Kr beams were determined based on a compromise between the stripped charge states and the stripping efficiency.The energy loss,energy straggling,and emittance growth due to stripping have a non-negligible impact on the transport of the stripped beams and the injection of the ring.Therefore,these parameters were simulated by GEANT4.In addition,the foil’s temperature evolution,which greatly affects the foil lifetime,was simulated by ANSYS.The maximum temperature of the foil bombarded by the U and Xe beams with the nominal parameters will exceed the safe value in terms of the impact of evaporation on the foil’s lifetime.Given the foil temperature constraint,the highest tolerable beam intensity and the injected ion number into the ring were derived for different beam sizes.The results of this paper will present important reference data for the optimization design and commissioning of the beamline and injection to the BRing for the stripped ions.

关键词： High-intensity heavy-ion accelerator facility Charge stripper Energy spread Thermal analysis Emittance growth Injection turns

Efficient adsorption separation of methane from C_(2)-C_(3) hydrocarbons in a Co(Ⅱ)-nodes metal-organic framework

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Chinese Journal of Chemical Engineering 2024年第5期69卷 192-198页

作者： jie zhang Xingzhe Guo Bing Lin Guangzu Xiong Hanshuang Wang Min zhang Liwen Fan Bingwen Li Shuisheng Chen Department of Chemistry and Chemical Engineering Taiyuan Institute of TechnologyTaiyuan 030008China Engineering Research Center of Oligosaccharides Fuyang Normal UniversityFuyang 236041China Shandong Key Laboratory of Biophysics Institute of BiophysicsDezhou UniversityDezhou 253023China

Methane(CH_(4))as a substitute for other mineral fuels plays a crucial role in reducing energy consumption and preventing environmental pollution.The present study employs a solvothermal method to fabricate a porous framework Co-metal-organic framework(Co-MOF)containing two distinct secondary building units(SBUs):an anionic[Co_(2)(μ_(2)-OH)(COO)_(4)(H_(2)O)]and a neutral[CoN_(2)(COO)_(2)].Notably,within the anionic SBUs,the coordinated water molecules induce the generation of divergent unsaturated Co(Ⅱ)centers in the unidirectional porous channels,thereby creating open metal sites.The adsorption performance of Co-MOF towards pure component gases was systematically investigated.The results demonstrated that Co-MOF exhibits superior adsorption capacity for C_(2)-C_(3) hydrocarbons compared to CH_(4),which offers the potential for efficient adsorption and separation of CH_(4) from C_(2)-C_(3) hydrocarbons.The gas selectivity separation ratios of Co-MOF for C_(2)H_(6)/CH_(4) and C_(3)H_8/CH_(4) were calculated using the ideal adsorbed solution theory method at 273/298 K and 0.1 MPa.The results revealed that Co-MOF achieved remarkable equilibrium separation selectivity for CH_(4) and C_(2)-C_(3) hydrocarbon gases among non-modified MOFs,signifying the potential of the synthesized Co-MOF for efficient recovery and purification of CH_(4) from C_(2)-C_(3) hydrocarbons.Breakthrough experiments further demonstrate the ability of Co-MOF to purify methane from C_(2)-C_(3) hydrocarbons in practical gas separation scenarios.Additionally,molecular simulation calculations further substantiate the propensity of anionic SBUs to interact with C_(2)-C_(3) hydrocarbon compounds.This study provides a novel paradigm for the development of porous MOF materials in the application of gas mixture separation.

关键词： Co-MOF Separation hydrocarbons Dynamic breakthrough curves Molecular simulations adsorbent Monte Carlo simulation

Ocular surface changes in moderate-to-severe acne vulgaris

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1049-1057页

作者： Ci-Yi Pan Dong-jie Sun Han-Ling Li Li Ma Min zhang Song-Yuan Tang Hui zhang Department of Ophthalmology First Affiliated Hospital of Kunming Medical UniversityKunming 650032Yunnan ProvinceChina Department of Dermatology First Affiliated Hospital of Kunming Medical UniversityKunming 650032Yunnan ProvinceChina Department of Stomatology the First People’s Hospital of Yunnan ProvinceKunming 650100Yunnan ProvinceChina Institute of Health Studies School of Public HealthKunming Medical UniversityKunming 650500Yunnan ProvinceChina

AIM:To investigate ocular surface disorders and tear function changes in patients with acne vulgaris and explore the potential relationship between acne vulgaris and dry eye.METHODS:This cross-sectional study included right eyes of 53 patients with acne vulgaris and 54 healthy controls.The participants completed the Ocular Surface Disease Index(OSDI)questionnaire.The following ocular surface-related parameters were measured:tear meniscus height(TMH),noninvasive tear breakup time(NIBUT),Schirmer I test(SIT),lipid layer thickness(LLT)score of the tear film,meibum score,meibomian gland orifice obstruction score,the ratio of meibomian gland loss,conjunctival hyperemia score,and corneal fluorescein staining(CFS)score.RESULTS:The stability of the tear film decreased in acne vulgaris patients.In the acne group,the TMH and NIBUT were lower,whereas the OSDI,meibum score,meibomian gland orifice obstruction score,ratio of meibomian gland loss,and conjunctival hyperemia score were higher compared with controls(P0.05).In two dry eye groups,the TMH,NIBUT,and LLT score were lower in the acne with dry eye(acne-DE)group,and the meibum score,meibomian gland orifice obstruction score,ratio of meibomian gland loss and conjunctival hyperemia score in the acne-DE group were higher(P0.05).CONCLUSION:Patients with moderate-to-severe acne vulgaris are more likely to experience dry eye than those without acne vulgaris.Reduced tear film stability and meibomian gland structure dysfunction are more pronounced in patients with moderate-to-severe acne and dry eye.

关键词： acne vulgaris meibomian gland dysfunction dry eye tear film

PPP1R14A is Associated with Immunotherapy Resistance in Head and Neck Squamous Cell Carcinoma Identified by Single-Cell and Bulk RNA-Sequencing

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Chinese Medical Sciences Journal 2024年第2期39卷 111-121页

作者： Jun-jie Ma Lei zhang Jin Lu Hao-Xuan zhang Department of Clinical Medicine Bengbu Medical UniversityBengbu 233030AnhuiChina Department of General Surgery The Second Affiliated Hospital of Bengbu Medical UniversityBengbu 233030AnhuiChina Department of Human Anatomy Bengbu Medical UniversityBengbu 233030AnhuiChina Anhui Key Laboratory of Computational Medicine and Intelligent Health Bengbu Medical UniversityBengbu 233030AnhuiChina

Objective To identify nivolumab resistance-related genes in patients with head and neck squamous cell carcinoma(HNSCC)using single-cell and bulk RNA-sequencing data.Methods The single-cell and bulk RNA-sequencing data downloaded from the Gene Expression Omnibus database were analyzed to screen out differentially expressed genes(DEGs)between nivolumab resistant and nivolumab sensitive patients using R software.The Least Absolute Shrinkage Selection Operator(LASSO)regression and Recursive Feature Elimination(RFE)algorithm were performed to identify key genes associated with nivolumab resistance.Functional enrichment of DEGs was analyzed with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses.The relationships of key genes with immune cell infiltration,differentation trajectory,dynamic gene expression profiles,and ligand-receptor interaction were explored.Results We found 83 DEGs.They were mainly enriched in T-cell differentiation,PD-1 and PD-L1 checkpoint,and T-cell receptor pathways.Among six key genes identified using machine learning algorithms,only PPP1R14A gene was differentially expressed between the nivolumab resistant and nivolumab sensitive groups both before and after immunotherapy(P0,P<0.05),lower differentiation of infiltrated immune cells(P<0.05),and a higher degree of interaction between HLA and CD4(P<0.05).Conclusions PPP1R14A gene is closely associated with resistance to nivolumab in HNSCC patients.Therefore,PPP1R14A may be a target to ameliorate nivolumab resistance of HNSCC patients.

关键词： PPP1R14A head and neck squamous cell carcinoma immunotherapy drug resistance

The role and applications of extracellular vesicles in osteoporosis

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Bone Research 2024年第1期12卷 62-77页

作者： Fei Fang jie Yang Jiahe Wang Tiantian Li Erxiang Wang Demao zhang Xiaoheng Liu Chenchen Zhou Institute of Biomedical Engineering West China School of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu 610041China State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengdu 610041China

Osteoporosis is a widely observed condition characterized by the systemic deterioration of bone mass and microarchitecture,which increases patient susceptibility to fragile fractures.The intricate mechanisms governing bone homeostasis are substantially impacted by extracellular vesicles(EVs),which play crucial roles in both pathological and physiological contexts.EVs derived from various sources exert distinct effects on osteoporosis.Specifically,EVs released by osteoblasts,endothelial cells,myocytes,and mesenchymal stem cells contribute to bone formation due to their unique cargo of proteins,miRNAs,and cytokines.Conversely,EVs secreted by osteoclasts and immune cells promote bone resorption and inhibit bone formation.Furthermore,the use of EVs as therapeutic modalities or biomaterials for diagnosing and managing osteoporosis is promising.Here,we review the current understanding of the impact of EVs on bone homeostasis,including the classification and biogenesis of EVs and the intricate regulatory mechanisms of EVs in osteoporosis.Furthermore,we present an overview of the latest research progress on diagnosing and treating osteoporosis by using EVs.Finally,we discuss the challenges and prospects of translational research on the use of EVs in osteoporosis.

关键词： osteoporosis homeostasis biomaterials

An envelope-based machine learning workflow for locating earthquakes in the southern Sichuan Basin

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Earthquake Research Advances 2024年第2期4卷 45-54页

作者： Kang Wang jie zhang Ji zhang zhangyu Wang Ziyu Li School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China

The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations.However,the application of machine learning to earthquake location problems faces challenges in regions with limited available training data.To address the issues of sparse event distribution and inaccurate ground truth in historical seismic datasets,we expand the training dataset by using a large number of synthetic envelopes that closely resemble real data and build an earthquake location model named ENVloc.We propose an envelope-based machine learning workflow for simultaneously determining earthquake location and origin time.The method eliminates the need for phase picking and avoids the accumulation of location errors resulting from inaccurate picking results.In practical application,ENVloc is applied to several data intercepted at different starting points.We take the starting point of the time window corresponding to the highest prediction probability value as the origin time and save the predicted result as the earthquake location.We apply ENVloc to observed data acquired in the southern Sichuan Basin,China,between September 2018 and March 2019.The results show that the average difference with the catalog in latitude,longitude,depth,and origin time is 0.02,0.02,2 km,and 1.25 s,respectively.These suggest that our envelope-based method provides an efficient and robust way to locate earthquakes without phase picking,and can be used in earthquake monitoring in near-real time.

关键词： Waveform envelope Earthquake location Local seismicity Synthetic data Sparse stations

Cu-substituted nickel hexacyanoferrate with tunable reaction potentials for superior ammonium ion storage

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Journal of Materials Science & Technology 2024年第2期169卷 19-27页

作者： Leiyu Fan Guangchang Shu Yiwen Liu Haoxiang Yu Lei Yan Liyuan zhang jie Shu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

In this work,a variety of Cu_(x)Ni_(2-x)Fe(CN)_(6)(x=0,0.4,0.8,1.2,1.6,2)cathodes for ammonium ion batteries are prepared and their electrochemical performances are investigated.During the introduction of copper in nickel hexacyanoferrate,the electrochemical performance varies without changing the structure of nickel hexacyanoferrate.The increase of Cu content in nickel hexacyanoferrate leads to the enhancement of reaction potential and capacity.Electrochemical results suggest that the substitution of Cu for Ni has a positive effect on improving the cycling stability and rate capacity of nickel hexacyanoferrate when x in Cu_(x)Ni_(2-x)Fe(CN)_(6)is less than 0.4.Therefore,Cu_(0.4)Ni_(1.6)Fe(CN)_(6)exhibits the best cycling per-formance(capacity retention of 97.54%at 0.3 C)and the highest rate capacity(41.4 mAh g^(-1)at 10 C)in Cu_(x)Ni_(2-x)Fe(CN)_(6).Additionally,the X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)tests also reveal that the structural evolution of Cu_(0.4)Ni_(1.6)Fe(CN)_(6)is highly reversible upon NH_(4)^(+)storage.Therefore,this work proposes a candidate material for ammoniumion batteries and offers a novel avenue for adjusting the operating potential of the material.

关键词： Nickel hexacyanoferrate Copper hexacyanoferrate NH_(4)^(+)storage Ammonium ion batteries Aqueous batteries

Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidative self-coupling of benzylamines

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 95-106页

作者： jie Chen Mingyuan Jian Deqiong Xie Kecan Dou Deli Chen Weidong Zhu Fumin zhang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

In this study,we synthesize a catalyst comprising cobalt nanoparticles supported on MXene by pyrolyzing a composite in a N2 environment.Specifically,the composite comprises a bimetallic Zn/Co zeolitic imidazole framework grown in situ on the outer surface of MXene.The catalytic efficiency of the catalyst is tested for the self-coupling of 4-methoxybenzylamine to produce value-added imine,where atmospheric oxygen(1 atm)is used as the oxidant.Based on the results,the catalyst displayed impressive catalytic activity,achieving 95.4%yield of the desired imine at 383 K for 8 h.Furthermore,the catalyst showed recyclability and tolerance toward benzylamine substrates with various functional groups.The outstanding performance of the catalyst is primarily attributed to the synergetic catalytic effect between the cobalt nanoparticles and MXene support,while also benefiting from the three-dimensional porous structure.Additionally,a preliminary investigation of potential reaction mechanisms is conducted.

关键词： MXene sacrificial template oxidative self-coupling Co nanoparticles imine

Development of RPA-Cas12a-fluorescence assay for rapid and reliable detection of human bocavirus 1

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Animal Models and Experimental Medicine 2024年第2期7卷 179-188页

作者： Weidong Qian Xuefei Wang Ting Wang jie Huang Qian zhang Yongdong Li Si Chen School of Food and Biological Engineering Shaanxi University of Science and TechnologyXi'anP.R.China Department of Dermatology Huazhong University of Science and Technology Union Shenzhen HospitalShenzhenP.R.China Ningbo Municipal Center for Disease Control and Prevention NingboP.R.China Medical College of Shenzhen University ShenzhenP.R.China

Human bocavirus(HBoV)1 is considered an important pathogen that mainly affects infants aged 6–24 months,but preventing viral transmission in resource-limited regions through rapid and affordable on-site diagnosis of individuals with early infection of HBoV1 remains somewhat challenging.Herein,we present a novel faster,lower cost,reliable method for the detection of HBoV1,which integrates a recombinase polymerase amplification(RPA)assay with the CRISPR/Cas12a system,designated the RPA-Cas12a-fluorescence assay.The RPA-Cas12a-fluorescence system can specifically detect target gene levels as low as 0.5 copies of HBoV1 plasmid DNA per microliter within 40 min at 37℃without the need for sophisticated instruments.The method also demonstrates excellent specificity without cross-reactivity to non-target pathogens.Furthermore,the method was appraised using 28 clinical samples,and displayed high accuracy with positive and negative predictive agreement of 90.9%and 100%,respectively.Therefore,our proposed rapid and sensitive HBoV1 detection method,the RPA-Cas12a-fluorescence assay,shows promising potential for early on-site diagnosis of HBoV1 infection in the fields of public health and health care.The established RPA-Cas12a-fluorescence assay is rapid and reliable method for human bocavirus 1 detection.The RPA-Cas12a-fluorescence assay can be completed within 40 min with robust specificity and sensitivity of 0.5 copies/μl.

关键词： CRISPR-Cas12a detection human bocavirus 1 on-site diagnosis recombinase polymerase amplification