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Overrun phenomenon and neutron yield in Coulomb explosion of deuterated alkane clusters driven by intense laser field

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Chinese Physics B 2018年第6期27卷 274-279页

作者： Hong-Yu li Mei-Dong Huang ming Kang De-Jun li College of Physics and Materials Science Tianjin Normal University Tianjin 300387 China

By using a simplified Coulomb explosion model, the laser-driven Coulomb explosion processes of three deuterated alkane clusters, i.e., deuterated methane（CD4）N, ethane（C2D6）N and propane（C3D8）N clusters are simulated *** overrun phenomenon that the deuterons overtake the carbon ions inside the expanding clusters, as well as the dependence of the energetic deuterons and fusion neutron yield on cluster size, is discussed in detail. Researches show that the average kinetic energy of deuterons and neutron yield generated in the Coulomb explosion of（C2D6）N cluster are higher than those of（CD4）N cluster with the same size, in qualitative agreement with the reported conclusions from the experiments of（C2 H6）N and（CH4）N clusters. It is indicated that（C2D6）N clusters are superior to（CD4）N clusters as a target for the laser-induced nuclear fusion reaction to achieve a higher neutron yield. In addition, by comparing the relevant data of（C3D8）N cluster with those of（C2D6）N cluster with the same size, it is theoretically concluded that（C3D8）N clusters with a larger competitive parameter might be a potential candidate for improving neutron generation. This will provide a theoretical basis for target selection in developing experimental schemes on laser-driven nuclear fusion in the future.

关键词： deuterated alkane cluster Coulomb explosion deuteron kinetic energy neutron yield

Comparison of visual outcomes with implantation of trifocal versus bifocal intraocular lens after phacoemulsification: a Meta-analysis

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 484-492页

作者： Juan-Juan Yang Qiu-Ping liu Jing-ming li li Qin Department of Ophthalmology First Affiliated Hospital of Xi'an Jiaotong University Department of Ophthalmology Affiliated Eye Hospital of Nanchang University

AIM： To compare a trifocal intraocular lens （IOL） and a bifocal IOL implantation in improving visual function after cataract surgery. METHODS： Eligible literatures were systematically searched through EMBASE and PubMed databases. The inclusion criteria were prospective comparative clinical trials on cataract surgery comparing trifocal IOL with bifocal IOL implantation that assessed visual acuity, contrast sensitivity and subjective vision quality. The effects were computed as standardized mean differences and pooled using fixed-effect or random-effect models. RESULTS： Four prospective randomized controlled trials （RCTs） and five cohorts provided data were included by a systematic review, comprising 265 eyes implanted with trifocal IOLs and 264 eyes implanted with bifocal IOLs. Monocular distance visual acuity （VA） showed a statistically significant but small difference that favored trifocal IOLs （MD=.0.06; 95%CI, -0.10 to -0.02; Z=2.90, P=0.004 for uncorrected distance VA, and MD- -0.02; 95%CI, -0.03 to .0.00; Z=2.02, P=0.04 for corrected distance VA）, but the data did not suggest that the effect of trifocal IOL implantation would clinically outperform bifocal IOL implantation. There was no significant difference in monocular near VA （MD=.0.01; 95%CI, -0.07 to 0.04; Z=0.42, P=-0.68 for distance-corrected near VA, and MD=-0.01; 95%CI, -0.06 to 0.03; Z=0.55, P=0.58 for corrected near VA） or refraction between two groups. Contrast sensitivity and subjective visual quality had no conclusive results. CONCLUSION： All results indicate that trifocal IOL and bifocal IOL had similar levels of monocular distance and near VA.

关键词： trifocal intraocular lens bifocal intraocularlens visual function Meta-analysis

Study on the Outdoor Wind Environment Simulation and Design Strategies of Rural Settlements in Cold Areas

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Journal of Harbin Institute of Technology(New Series) 2014年第5期21卷 72-76页

作者： ming li Hong Jin Xin-Yu Zhang School of Architecture Harbin Institute of Technology

To improve the outdoor environment of rural settlement and reduce the energy consumption of rural houses in winterin cold areas,the seriously bad wind environment should been controlled and considered. This paper applies the method of numerical simulation to simulate the wind environment of some typical arrangement of building and courtyard in winter,and concludes the optimal building and courtyard arrangement types and strategies. It aims to provide some technical supports for improving the wind environment of rural settlements in cold regions.

关键词： rural settlements wind environment microclimate simulation analysis planning strategies

Towards Efficient Electromagnetic Interference Shielding Performance for Polyethylene Composites by Structuring Segregated Carbon Black/Graphite Networks

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Chinese Journal of Polymer Science 2016年第12期34卷 1490-1499页

作者： Cheng-hua Cui 鄢定祥 Huan Pang li-chuan Jia Yu Bao Xin Jiang Zhong-ming li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

An electromagnetic interference （EMI） shielding composite based on ultrahigh molecular weight polyethylene （UHMWPE） loaded with economical graphite-carbon black （CB） hybrid fillers was prepared via a green and facile methodology, i.e., high-speed mechanical mixing combined with hot compression thus avoiding the assistance of the intensive ultrasound dispersion in volatile organic solvents. In this composite, the graphite-CB hybrid fillers were selectively distributed in the interfacial regions of UHMWPE domains resulting a typical segregated structure. Thanks to the specific morphology of segregated conductive networks along with the synergetic effect of large-sized graphite flakes and small-sized CB nanoparticles, a low filler loading of 7.7 vol% （15 wt%） yielded the graphite-CB/UHMWPE composites with a satisfactory electrical conductivity of 33.9 S/m and a superior shielding effectiveness of 40.2 dB, manifesting the comparable value of the pricey large-aspect-ratio carbon nanofillers （e.g., carbon nanotubes and graphene nanosheets） based polymer composites. More interestingly, with the addition of 15 wt% graphite-CB （1/3, W/W） hybrid fillers, the tensile strength and elongation at break of the composite reached 25.3 MPa and 126%, respectively; with a remarkable increase of 58.1% and 2420% over the conventional segregated graphite/UHMWPE composites. The mechanical reinforcement could be attributed to the favor of the small-sized CB particles in the polymer molecular diffusion between UHMWPE domains which in tuna provided a stronger interfacial adhesion. This work provides a facile, green and affordable strategy to obtain the polymer composites with high electrical conductivity, efficient EMI shielding, and balanced mechanical performance.

关键词： Graphite Carbon black Segregated structure Electromagnetic interference Synergistic effect.

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纤维增强混凝土的耐久性能研究现状简述

广州建筑 2024年第7期52卷 116-120页

作者：周振陈伟智李钢粮何明理李海燕广东永和建设集团有限公司广州510330 广东工业大学土木与交通工程学院广州510006

随着建筑要求的不断提高和混凝土研究的发展,纤维增强混凝土作为一种高性能的新型材料,越来越受到土木行业的欢迎。本文将从抗氯离子侵蚀性、抗渗透、抗冻融和抗碳化性能这四个方面来综述近年来国内外关于纤维对混凝土耐久性影响的研究... 详细信息

随着建筑要求的不断提高和混凝土研究的发展,纤维增强混凝土作为一种高性能的新型材料,越来越受到土木行业的欢迎。本文将从抗氯离子侵蚀性、抗渗透、抗冻融和抗碳化性能这四个方面来综述近年来国内外关于纤维对混凝土耐久性影响的研究进程,分析并总结在渗透、氯离子侵蚀性、冻融和碳化环境下,纤维对混凝土耐久性能影响机理。

关键词：纤维增强混凝土抗氯离子侵蚀性抗冻融抗碳化抗渗透

RESID HYDROCONVERSION—A NEW APPROACH IN PROCESSING INFERIOR RESIDUAL OILS

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石油学报（石油加工） 2001年第1期17卷 35-41页

作者： li Zhi qiang, liU Jia ming, SUN li li (Beijing Design Institute, SINOPEC, Beijing 100724, China) 中国石油化工公司北京设计所北京 100724 中国石油化工总公司北京设计所北京 100724

In order to meet the market demands for more premium distillates and the more stringent requirements of environment protection, China refineries should find a better way for deep processing of residues. This paper describes the necessity, overview and application of the resid hydroconversion process in China. Qilu Petrochemical Co. built the first vacuum resid hydrodesulfurization (VRDS) unit with a capacity of 840 kt/a of Gudao vacuum residue in 1986. And Dalian West Pacific Petrochemical Co. Ltd. built the first atmospheric resid hydrodesulfurization (ARDS) unit with the capacity of 2 Mt/a in 1992. Beijing Design Institute SINOPEC did the engineering design of these two units. Some modifications on the units were carried out, which gives the adaptability and flexibility in processing inferior crudes such as high sulfur crudes.

关键词：加氢裂化残油市场需求环境保护

liver injury in COVID-19: Clinical features, potential mechanisms, risk factors and clinical treatments

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World Journal of Gastroenterology 2023年第2期29卷 241-256页

作者： Shu-Wu Zhao Yi-ming li Yi-lin li Chen Su Department of Anesthesiology Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of MedicineChangsha 410013Hunan ProvinceChina School of Basic Medical Science Naval Medical University/Second Military UniversityShanghai 200433China Department of Pathology Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of MedicineChangsha 410013Hunan ProvinceChina Department of Anesthesiology and Pain Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of MedicineChangsha 410013Hunan ProvinceChina

The coronavirus disease 2019(COVID-19)pandemic has been a serious threat to global health for nearly 3 *** addition to pulmonary complications,liver injury is not uncommon in patients with novel *** the prevalence of liver injury varies widely among COVID-19 patients,its incidence is significantly increased in severe ***,there is an urgent need to understand liver injury caused by *** features of liver injury include detectable liver function abnormalities and liver imaging *** function tests,computed tomography scans,and ultrasound can help evaluate liver *** factors for liver injury in patients with COVID-19 include male sex,preexisting liver disease including liver transplantation and chronic liver disease,diabetes,obesity,and *** date,the mechanism of COVID-19-related liver injury is not fully *** pathophysiological basis can generally be explained by systemic inflammatory response,hypoxic damage,ischemia-reperfusion injury,and drug side *** this review,we systematically summarize the existing literature on liver injury caused by COVID-19,including clinical features,underlying mechanisms,and potential risk ***,we discuss clinical management and provide recommendations for the care of patients with liver injury.

关键词： liver injury COVID-19 Clinical feature Risk factor Treatment and management strategy

Influence of severity and types of astigmatism on visual acuity in school-aged children in southern China

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International Journal of Ophthalmology(English edition) 2018年第8期11卷 1377-1383页

作者： li-li Wang Wei Wang Xiao-Tong Han ming-Guang He Zhongshan Ophthalmic Center State Key Laboratory of OphthalmologySun Yat-Sen University

AIM： To investigate the influence of astigmatism on visual acuity in school-aged children, and to define a cutoff for clinically significant astigmatism. METHODS： This is a population-based, cross-sectional study. Among 5053 enumerated children aged 5-15 y in Guangzhou, 3729（73.8%） children aged 7-15 with successful cycloplegic auto-refraction（1% cyclopentolate） and a reliable visual acuity measurement were included. Ocular measurement included external eye, anterior segment, media and fundus and cycloplegic auto-refraction. Primary outcome measures included the relationship between severity and subtypes of astigmatism and the prevalence of visual impairment. Three criteria for visual impairment were adopted： best-corrected visual acuity（BCVA） ≤0.7, uncorrected visual acuity（UCVA） ≤0.5 or 〈0.7 in the right ***： Increases of cylinder power was significantly associated with worse visual acuity（UCVA： β=0.051, P〈0.01; BCVA： β=0.025, P〈0.001）. A substantial increase in UCVI and BCVI was seen with astigmatism of 1.00 diopter（D） or more. Astigmatism ≥1.00 D had a greater BCVI prevalence than cylinder power less than 1.00 D（OR=4.20, 95%CI： 3.08-5.74）, and this was also true for hyperopic, emmetropic and myopic refraction categories. Oblique astigmatism was associated with a higher risk of BCVI relative to with the rule astigmatism in myopic refractive category（OR=12.87, 95%CI： 2.20-75.38）.CONCLUSION： Both magnitude and subtypes of astigmatism influence the prevalence of visual impairment in school children. Cylinder ≥1.00 D may be useful as a cutoff for clinically significant astigmatism.

关键词： astigmatism visual acuity children population-based study

The investigation of NTO/HMX-based plastic-bonded explosives and its safety performance

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Defence Technology（防务技术） 2022年第1期18卷 72-80页

作者： li-xiaosong Du Shao-hua Jin Qing-hai Shu li-jie li Kun Chen ming-lei Chen Jun-feng Wang School of Materials Science and Engineering Beijing Institute of Technology Beijing China Garsu Yinguang Chemical Industry Group Coltd Baiyin China State Key Laboratory of Explosion Science and Technobogy Beijing Institute of TechnologyBeijing China

3-nitro-1,2,4-triazol-5-one(NTO)is the main component of insensitive munitions(IM)formulation because of its outstanding insensitive *** this paper,a series of NTO/HMX-based compositeexplosives were prepared and *** study focuses on the effect of NTO on the perfommance of the formulations,especially the safety *** results revealed that the mechanical sensi-tivity of fomulations was associated with NTO content,as well as the thermal conductivity,specific heat capacity and Arrhenius ***,the high amount of NTO using in formulation was proved to be helpful for NTO/HMX-based formulation to exhibit good thermal ***,by accelerating rate calorimeter(ARC)and a modified cook-off equipment,the pressure and pressure rise rate were proved as the important indicator for judging the thermal safety performance in confined ***,the numerical simulation was used as a credible method for predicting the respond temperature of cook-off experiment.

关键词： 3-nitro-1,2,4-triazol-5-one(NTO) Plastic-bonded explosive(PBX) Safety performance Cook-off