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Photonuclear production of nuclear isomers using bremsstrahlung induced by laser-wakefield electrons

Nuclear Science and Techniques 2023年第5期34卷 112-124页

作者： Hao-Yang Lan Di Wu Jia-Xin Liu Jian-Yao Zhang huan-gang lu Jian-Feng Lv Xue-Zhi Wu Wen luo Xue-Qing Yan State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China School of Nuclear Science and Technology University of South ChinaHengyang 421001China

In this study,we theoretically investigate the feasibility of using laser-wakefield accelerated(LWFA)electrons for the photonuclear measurement of nuclear isomers according to the characteristics of the electrons obtained from LWFA experiments conducted at the Compact Laser-Plasma Accelerator(CLAPA)laboratory.The experiments at the CLAPA show that a stable electron beam with an energy of 78-135 MeV and a charge of 300-600 pC can be obtained.The bremsstrahlung spectra were simulated using Geant4,which suggests that a bremsstrahlung source with a peak intensity of 10^(19) photons/s can be generated.Theoretical calculations of isomer production cross sections from the photonuclear reactions on six target nuclei,^(197)Au,^(180)Hf,^(159)Tb,^(115)In,^(103)Rh,and ^(90)Zr,were performed and compared with the available experimental data in EXFOR,which suggest that further experiments are required for a series of photonuclear reaction channels.Flux-averaged cross sections and isomer ratios(IR)resulting from such bremsstrahlung sources are theoretically deduced.The results suggest that IR measurements can be used to constrain nuclear components,such asγstrength function and optical model potential.In addition,the detection of the decay characteristics was evaluated with Geant4 simulations.The use of the LWFA electron beam and its bremsstrahlung for photonuclear studies involving nuclear isomers is anticipated.

关键词： Photonuclear reactions Laser–plasma acceleration Flux-averaged isomer ratio

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Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo Dong huan lu Hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in soil.Its spatial distribution and environment risk assessment are extremely important for the management and remediation of HMs.Eighty soil samples were collected from the high-sulfur CG site in northern China and analyzed for six HMs.The results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment code.The semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of HMs.Fe,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more uniform.The spatial autocorrelation indicated that all HMs had strong spatial heterogeneity.The BCR sequential extraction was employed to qualify the geochemical fractions of HMs.The data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)fractions.Pearson correlation analysis showed that pH was the main control factor affecting the non-residue fractions of HMs.Therefore,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of HMs.Finally,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

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Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： Xing Chen Yong-gang lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in water.The findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying exponentially.Increasing the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the JPC.The optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in water.Material density plays a crucial role in the velocity decay pattern of the JPC during penetration.JPC with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are similar.Consequently,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge warhead.Finally,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

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Wearable multilead ECG sensing systems using on-skin stretchable and breathable dry adhesives

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Bio-Design and Manufacturing 2024年第2期7卷 167-180页

作者： Yingxi Xie Longsheng lu Wentao Wang huan Ma School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China College of Automotive and Mechanical Engineering Changsha University of Science and TechnologyChangsha 410114China Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangzhou 510080China

Electrocardiogram(ECG)monitoring is used to diagnose cardiovascular diseases,for which wearable electronics have attracted much attention due to their lightweight,comfort,and long-term use.This study developed a wearablemultilead ECG sensing system with on-skin stretchable and conductive silver(Ag)-coated fiber/silicone(AgCF-S)dry adhesives.Tangential and normal adhesion to pigskin(0.43 and 0.20 N/cm2,respectively)was optimized by the active control of fiber density and mixing ratio,resulting in close contact in the electrode–skin interface.The breathableAgCF-S dry electrodewas nonallergenic after continuous fit for 24 h and can be reused/cleaned(>100 times)without loss of adhesion.The AgCF encapsulated inside silicone elastomers was overlapped to construct a dynamic network under repeated stretching(10%strain)and bending(90°)deformations,enabling small intrinsic impedance(0.3,0.1 Hz)and contact impedance variation(0.7 k)in high-frequency vibration(70 Hz).All hard/soft modules of the multilead ECG system were integrated into lightweight clothing and equipped with wireless transmission for signal visualization.By synchronous acquisition of I–III,aVR,aVL,aVF,and V4 lead data,the multilead ECG sensing system was suitable for various scenarios,such as exercise,rest,and sleep,with extremely high signal-to-noise ratios.

关键词： Multilead electrocardiogram Dry electrodes Wearable electronics Wireless transmission

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Renewable biosynthesis of isoprene from wastewater through a synthetic biology approach:the role of individual organic compounds

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 13-24页

作者： Min Yang Xianghui Li Weixiang Chao Xiang Gao huan Wang lu lu State Key Laboratory of Urban Water Resource and Environment School of Civil and Environmental EngineeringHarbin Institute of TechnologyShenzhen 518055China Center for Materials Synthetic Biology CAS Key Laboratory of Quantitative Engineering Biology of CASShenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academic of ScienceShenzhen 518000China Institute of Urban Ecology and Environmental Technology School of Materials and Environmental EngineeringShenzhen Polytechnic UniversityShenzhen 518055China

The biosynthesis of isoprene offers a more sustainable alternative to fossil fuel-based approaches,yet its success has been largely limited to pure organic compounds and the cost remains a challenge.This study proposes a waste-to-wealth strategy for isoprene biosynthesis utilizing genetically engineered E.coli bacteria to convert organic waste from real food wastewater.The impact of organic compounds present in wastewater on E.coli growth and isoprene production was systematically investigated.The results demonstrated that with filtration pretreatment of wastewater,isoprene yield,and production achieved 115 mg/g COD and 7.1 mg/(L·h),respectively.Moreover,even without pretreatment,isoprene yield only decreased by~24%,indicating promising scalability.Glucose,maltose,glycerol,and lactate are effective substrates for isoprene biosynthesis,whereas starch,protein,and acetate do not support E.coli growth.The optimum C/N ratio for isoprene production was found to be 8:1.Furthermore,augmenting essential nutrients in wastewater elevated the isoprene yield increased to 159 mg/g COD.The wastewater biosynthesis significantly reduced the cost(44%–53%decrease,p-valuelue<0.01)compared with both sugar fermentation and fossil fuel–based refining.This study introduced a more sustainable and economically viable approach to isoprene synthesis,offering an avenue for resource recovery from wastewater.

关键词： Wastewater Resource recovery Genetic engineering Biosynthesis Isoprene

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Fluid-structure interaction simulation for multi-body flexible morphing structures

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Chinese Journal of Aeronautics 2024年第2期37卷 137-147页

作者： Wenzhi GUO Yongtao SHUI lu NIE gang CHEN State Key Laboratory of Strength and Vibration for Mechanic Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Launch Vehicle Technology Beijing 100076China China Academy of Aerospace Science and Innovation Beijing 100086China Shannxi Key Laboratory of Service Environment and Control for Flight Vehicles Xi’an Jiaotong UniversityXi’an 710049China

The multi-body flexible morphing airfoil can improve the aerodynamic characteristics based on different flight missions continuously.Recently researches have focused on the unsteady aerodynamic characteristics of flexible wings under passive actuation.However,the unsteady aerodynamic characteristics with the fluid-structure interaction effects in the multi-body active actuation process of morphing airfoil deserve further investigation.In this paper,a fluid-structure coupled simulation method for multi-body flexible morphing airfoil with active actuation subsystem was investigated,and the aerodynamic characteristics during deformation were compared with different skin flexibility,flow field environment,actuation mode and actuation time.The numerical results show that for the steady aerodynamic,the skin flexibility can improve the stability efficiency.In the unsteady process,the change trend of the transient lift coefficient and pitching moment are consistent with those of the active drive characteristics,while the instantaneous lift-drag ratio coefficient is greatly affected by the driving mode and can be improved by increasing the driving duration.

关键词： Fluid-structure interaction Multi-body dynamics modeling Flexible structures Aerodynamics Morphing wings

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The risk factors and threshold level of subchronic inhalation exposure of reclaimed water

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Journal of Environmental Sciences 2024年第3期137卷 639-650页

作者： Jiayang Kong Yun lu Yunru Ren Menghao Chen gang Liu Liangliang Shi State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute exposure.Subchronic exposure has also been shown to induce infammatory responses with visible tissue damage.However,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is necessary.In this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed water.Accordingly,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A levels.Moreover,infammation persisted after a 4-week recovery period.The calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/day.Meanwhile,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed water.The threshold level of endotoxin was lower than that in most non-potable reclaimed water.The findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.

关键词： Reclaimed water Inhalation exposure Risk factor Threshold Infammation Endotoxin

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Facile intercalation of alkali ions in WO_(3)for modulated electronic and optical properties:Implications for artificial synapses and chromogenic application

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 149-160页

作者： Changmeng huan Zihan lu Silin Tang Yongqing Cai Qingqing Ke School of Microelectronics Science and Technology Sun Yat-sen UniversityZhuhai 519082China Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen UniversityZhuhai 519082China Institute of Applied Physics and Materials Engineering University of MacaoTaipaMacao 999078China

Tungsten oxides(WO_(3))are widely recognized as multifunctional systems owing to the existence of rich polymorphs.These diverse phases exhibit distinct octahedra-tilting patterns,generating substantial tunnels that are ideally suited for iontronics.However,a quantitative comprehension regarding the impact of distinct phases on the kinetics of intercalated conducting ions remains lacking.Herein,we employ first-principles calculations to explore the spatial and orientational correlations of ion transport inγ-and h-WO_(3),shedding light on the relationship between diffusion barriers and the size of the conducting ions.Our findings reveal that different types and concentrations of alkali-metals induce distinct and continuous lattice distortions in WO_(3)polymorphs.Specifically,γ-WO_(3)is more appropriate to accommodate Li+ions,exhibiting a diffusion barrier and coefficient of 0.25 eV and 9.31×10^(-8)cm^(2)s^(-1),respectively.Conversely,h-WO_(3)features unidirectional and sizeable tunnels that facilitate the transport of K+ions with an even lower barrier and a high coefficient of 0.11 e V and 2.12×10^(-5)cm^(2)s^(-1),respectively.Furthermore,the introduction of alkali-metal into WO_(3)tunnels tends to introduce n-type conductivity by contributing s-electrons to the unoccupied W 5d states,resulting in enhanced conductivity and tunable electronic structures.These alkali metals in WO_(3)tunnels are prone to charge transfer,forming small polaronic states and modulating the light absorption in the visible and nearinfrared regions.These tunable electronic and optical properties,combined with the high diffusion coefficient,underscore the potential of WO_(3)in applications such as artificial synapses and chromogenic devices.

关键词： WO_(3)polymorphs ion insertion kinetic activity tunable electronic and optical properties iontronics

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Possible Role of Cellular Polyamine Metabolism in Neuronal Apoptosis

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Current Medical Science 2024年第2期44卷 281-290页

作者： Xin-tong JI Wen-lei YU Meng-jia JINI Lin-jie lu Hong-ping YIN huan-huan WANG School of Basic Medical Sciences Affiliated Hospital of Hangzhou Normal UniversityHangzhou Normal UniversityHangzhou 311121China School of Medicine Chongqing UniversityChongqing 400030China Department of Stomatology Huzhou Wuxing District People's HospitalHuzhou Wuxing District Maternal and Child Health HospitalHuzhou 313008China School of Pharmacy Zhejiang UniversityHangzhou 310030 China'Department of Stomatology Haining Hospital of Traditional Chinese MedicineJiaxing 314400China

Recent studies have shown that cellular levels of polyamines(PAs)are significantly altered in neurodegenerative diseases.Evidence from in vivo animal and in vitro cell experiments suggests that the cellular levels of various PAs may play important roles in the central nervous system through the regulation of oxidative stress,mitochondrial metabolism,cellular immunity,and ion channel functions.Dysfunction of PA metabolism related enzymes also contributes to neuronal injury and cognitive impairment in many neurodegenerative diseases.Therefore,in the current work,evidence was collected to determine the possible associations between cellular levels of PAs,and related enzymes and the development of several neurodegenerative diseases,which could provide a new idea for the treatment of neurodegenerative diseases in the future.

关键词： polyamine apoptosis mitochondria neurodegenerative disease

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Aspartoacylase suppresses prostate cancer progression by blocking LYN activation

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Military Medical Research 2024年第2期11卷 180-205页

作者： Hong Weng Kang-Ping Xiong Wang Wang Kai-Yu Qian Shuai Yuan gang Wang Fang Yu Jun luo Meng‑Xin lu Zhong‑Hua Yang Tao Liu Xing huang Hang Zheng Xing-huan Wang Department of Urology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Center for Evidence‑Based and Translational Medicine Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Biological Repositories Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Key Laboratory of Tumor Biological Behaviors Wuhan 430071China Department of Pathology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Center for Pathology and Molecular Diagnostics Wuhan UniversityWuhan 430071China Wuhan Research Center for Infectious Diseases and Cancer Chinese Academy of Medical SciencesWuhan 430071China

Background:Globally,despite prostate cancer(PCa)representing second most prevalent malignancy in male,the precise molecular mechanisms implicated in its pathogenesis remain unclear.Consequently,elucidating the key molecular regulators that govern disease progression could substantially contribute to the establishment of novel therapeutic strategies,ultimately advancing the management of PCa.Methods:A total of 49 PCa tissues and 43 adjacent normal tissues were collected from January 2017 to December 2021 at Zhongnan Hospital of Wuhan University.The advanced transcriptomic methodologies were employed to identify differentially expressed mRNAs in PCa.The expression of aspartoacylase(ASPA)in PCa was thoroughly evaluated using quantitative real-time PCR and Western blotting techniques.To elucidate the inhibitory role of ASPA in PCa cell proliferation and metastasis,a comprehensive set of in vitro and in vivo assays were conducted,including orthotopic and tumor-bearing mouse models(n=8 for each group).A combination of experimental approaches,such as Western blotting,luciferase assays,immunoprecipitation assays,mass spectrometry,glutathione S-transferase pulldown experiments,and rescue studies,were employed to investigate the underlying molecular mechanisms of ASPA's action in PCa.The Student‘s t-test was employed to assess the statistical significance between two distinct groups,while one-way analysis of variance was utilized for comparisons involving more than two groups.A two-sided P<0.05 was deemed to indicate statistical significance.Results:ASPA was identified as a novel inhibitor of PCa progression.The expression of ASPA was found to be significantly down-regulated in PCa tissue samples,and its decreased expression was independently associated with patients’prognosis(HR=0.60,95%CI 0.40–0.92,P=0.018).Our experiments demonstrated that modulation of ASPA activity,either through gain-or loss-of-function,led to the suppression or enhancement of PCa cell proliferation,migration,and invasion,respectively.The inhibitory

关键词： Prostate cancer Aspartoacylase LYN JNK AP-1 C-Jun Phosphorylation

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