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Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

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Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： ya yang Xiangzhen Kong qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble

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Nuclear Science and Techniques 2024年第3期35卷 216-227页

作者： Deng Liu Alam Noor A zhen-zhen qin yang Lei School of Mathematics and Physics Southwest University of Science and TechnologyMianyang 621010China School of Nuclear Science and Technology Southwest University of Science and TechnologyMianyang 621010China

The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output *** quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the ***,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists.

关键词： Neural network Two-body random ensemble Spin distribution of nuclear ground state

Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong Hui Li ya‑qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Insight into vertical piezoelectric characteristics regulated thermal transport in van der Waals two-dimensional materials

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Rare Metals 2024年第2期43卷 770-779页

作者： Dong-Hai Wei E Zhou Jin-Yuan Xu Hui-Min Wang Chen Shen Hong-Bin Zhang zhen-zhen qin Guang-Zhao qin State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China Hunan Key Laboratory for Micro-Nano Energy Materials and Device and School of Physics and Optoelectronics Xiangtan UniversityXiangtan411105China Institute of Materials Science Technical University of DarmstadtAlarich-Weiss-Str.264287DarmstadtGermany School of Physics and Microelectronics Zhengzhou UniversityZhengzhou450001China

The urgent demand of extreme(ultra-high/low)thermal conductivity materials is triggered by the high-power device,where exploring the theories and mechanisms of regulating thermal transport properties plays a key ***,we elaborately investigate the effect of vertical(out-of-plane)piezoelectric characteristics on thermal transport,which is historically *** different stacking-order(AA and AB)bilayer boron nitride(Bi-BN)in two-dimensional(2D)materials are selected as study *** performing state-of-the-art first-principles calculations,it is found that the polarization charge along the out-of-plane orientation ascends significantly with the increasing piezoelectric response in AB stacked Bi-BN(Bi-BN-AB)followed by the enhanced interlayer B–N atomic ***,the amplitude of phonon anharmonicity in Bi-BN-AB increases larger than that in the AA stacked Bi-BN(Bi-BN-AA),resulting in the dramatic weakening of the thermal conductivity by 20.34%under 18%*** research reveals the significant role of the vertical(out-of-plane)piezoelectric characteristic in regulating thermal transport and provides new insight into accurately exploring the thermal transport performance of 2D van der Waals materials.

关键词： Thermal conductivity Piezoelectric effect 2D materials Bilayer BN Strain engineering

Maximum initial primary wave model for low-Froude-number reservoir landslides based on wave theory

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Journal of Mountain Science 2024年第8期21卷 2664-2680页

作者： LI yang HUANG Bolin qin zhen DONG Xingchen HU Lei National Field Observation and Research Station of Landslides in Three Gorges Reservoir Area of yangtze River Yichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China

The impulse waves induced by large-reservoir landslides can be characterized by a low Froude ***,systematic research on predictive models specifically targeting the initial primary wave is *** the Shuipingzi 1#landslide that occurred in the Baihetan Reservoir area of the Jinsha River in China as an engineering example,this study established a large-scale physical model(with dimensions of 30 m×29 m×3.5 m at a scale of 1:150)and conducted scaled experiments on 3D landslide-induced impulse *** the process in which a sliding mass displaced and compressed a body of water to generate waves,the maximum initial wave amplitude was found to be positively correlated with the sliding velocity and the volume of the *** the increase in the water depth,the wave amplitude initially increased and then *** duration of pressure exertion by the sliding mass at its maximum velocity directly correlated with an elevated wave *** on the theories of low-amplitude waves and energy conservation,while considering the energy conversion efficiency,a predictive model for the initial wave amplitude was *** model could fit and validate the functions of wavelength and wave *** accuracy of the initial wave amplitude was verified using physical experiment data,with a prediction accuracy for the maximum initial wave amplitude reaching 90%.The conversion efficiency(η)directly determined the accuracy of the estimation *** clear conditions for landslide-induced impulse wave generation,estimating the value ofηthrough analogy cases was *** study has derived the landslide-induced impulse waves amplitude prediction formula from the standpoints of wave theory and energy conservation,with greater consideration given to the intrinsic characteristics in the formation process of landslide-induced impulse waves,thereby enhancing the applicability and extensibility of the *** can facilitate the development

关键词： Three-dimensional physical model experiments Reservoir-landslide-induced impulse wave Energy conversion efficiency Landslide-induced impulse wave prediction model Shuipingzi 1#landslide

Quality of life after pancreatic surgery

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World Journal of Gastroenterology 2024年第8期30卷 943-955页

作者： Shi-zhen Li Ting-Ting zhen Yi Wu Min Wang Ting-Ting qin Hang Zhang Ren-Yi qin Department of Biliary-Pancreatic Surgery Affiliated Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Pancreatic surgery is challenging owing to the anatomical characteristics of the *** attention has been paid to changes in quality of life(QOL)after pancreatic *** To summarize and analyze current research results on QOL after pancreatic *** A systematic search of the literature available on PubMed and EMBASE was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** studies were identified by screening the references of retrieved *** on patients’QOL after pancreatic surgery published after January 1,2012,were *** included prospective and retrospective studies on patients'QOL after several types of pancreatic *** results of these primary studies were summarized *** A total of 45 articles were included in the study,of which 13 were related to pancreaticoduodenectomy(PD),seven to duodenum-preserving pancreatic head resection(DPPHR),nine to distal pancreatectomy(DP),two to central pancre-atectomy(CP),and 14 to total pancreatectomy(TP).Some studies showed that 3-6 months were needed for QOL recovery after PD,whereas others showed that 6-12 months was more *** TP and PD had similar influences on QOL,patients needed longer to recover to preoperative or baseline levels after *** QOL was better after DPPHR than ***,the superiority of the QOL between patients who underwent CP and PD remains *** decrease in exocrine and endocrine functions postoperatively was the main factor affecting the *** invasive surgery could improve patients’QOL in the early Core Tip:This review summarizes and analyzes current research results on quality of life(QOL)after pancreatic *** article covers the discussion and analysis of the QOL of various pancreatic *** kind of surgical procedure has better QOL is *** long-term benefits on QOL of minimally invasive su

关键词： Quality of life Pancreaticoduodenectomy Duodenum-preserving pancreatic head resection Distal pancreatectomy Central pancreatectomy Total pancreatectomy

Prevalence of Cannabis Use around the World:A Systematic Review and Meta-Analysis,2000-2024

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China CDC weekly 2024年第25期6卷 597-604,I0013,I0014页

作者： Qianning Wang zhen qin Xing Xing He Zhu Zhongwei Jia National Institute of Health Data Science Center for Drug Abuse Prevention and ControlPeking UniversityBeijingChina School of Public Health Peking UniversityBeijingChina

This study aims to perform a systematic review and meta-analysis on the global prevalence of cannabis use to inform drug prevention strategies,policy-making,and resource *** study initially screened 177,843 studies published between January 1,2000,and January 15,2024,using peer-reviewed databases including Web of Science,PubMed,Scopus,Embase,and Cochrane ***,595 studies were identified for data extraction,and 39 of these were selected as country-representative *** among the selected studies was assessed using the chi-squared test and I2 statistic,while sensitivity analysis was conducted to evaluate the robustness of the *** prevalence of cannabis use varied between 0.42%and 43.90%across 33 European countries,1.40%to 38.12%across 15 North and South American countries,0.30%to 19.10%across 16 Asian countries,and 1.30%to 48.70%across 18 Oceania and African *** pooled prevalence of cannabis use was 12.0%[95%confidence interval(CI):10.0,14.3]in countries where cannabis is legalized,compared to 5.4%(95%CI:4.3,6.9)in non-legalized *** findings indicate that the prevalence of cannabis use has disproportionately increased in most countries with the implementation of medical or recreational cannabis legalization policies and relevant geographic *** efforts are needed to monitor newly cannabis-legalized countries and prevent initial use.

关键词： prevention legal initially

Antibonding orbital tailor and stress relief engineering for FeS2 complex toward superior sodium storage

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Rare Metals 2024年第10期43卷 5048-5059页

作者： You-Bin Zhang zhen-Guo Qi Fu-Sheng Liu Guo-Hui qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology Shandong Synergetic Innovation Center of Ecological and Chemical Engineering

The sluggish kinetics behaviors and vast volume variations of Na+hosts to FeS2anode involved intercalation,and conversion reactions plague its applicability of sodium-ion batteries （SIBs）.Here,a significantly expedited kinetics via cation intercalation and considerably relieved stress accumulation by constructing the concave scaffold protector are approached for *** Mn2+intercalation into FeS2,a new stable Mn–FeS2was generated with distorted coordination;elevated antibonding orbital occupancy and lowed d band center to the release of more free Na+were achieved,which was further encapsulated by hollow bowl-like carbon spheres （BC）This cation intercalation and concave morphology strategies confer Mn–FeS2@BC significantly enhanced electron ion transport kinetics via reversed electron transfer to FeS2fast desolvation kinetics,and evidently depressed structural deformation during Na+insertion and ***,Mn–FeS2@BC delivers the longevity and stable Na+storage capacity in both half and full cell ***,Mn–FeS2@BC also displays excellen adaptability in a wider temperature *** work proposes new views into the deep regulation of electrochemical performance of transition metal anodes via intercalation chemistry and concave engineering.

关键词： Concave engineering FeS2 Intercalation chemistry Sodium capture

Complete response of myeloid/lymphoid neoplasms with PDGFRA rearrangement presenting as leukemia/myeloid sarcoma to imatinib monotherapy

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Chinese Medical Journal 2019年第20期132卷 2498-2500页

作者： Rui Ma Xiao-Jun Huang Jin-Song Jia Jun Kong ya-zhen qin Hao Jiang Peking University Institute of Hematology Peking University People's HospitalBeijing 100044China

To the Editor: The presence of FIP-1-like-1-platelet-derived growth factor receptor-α (FIP1L1-PDGFRA, F/P) fusion gene accounts for approximately 23% (3%-56%) of all eosinophilias.[1] From 2008, the World Health Organization (WHO) classification redefined this disease as "myeloid/lymphoid neoplasms with eosinophilia and PDGFRA rearrangement," now constituting a distinct type of hematopoietic disorders. F/P fusion is a tyrosine kinase and is therefore sensitive to tyrosine kinase inhibitors (TKIs).

关键词： neoplasms myeloid PDGFRA