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地下水示踪试验中穿透曲线的解析——以平果县平南赤泥堆场地下岩溶系统为例

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地下水 2024年第2期46卷 9-12页

作者：韦栋文王文海桂林理工大学环境科学与工程学院广西桂林541006

地下水示踪试验中的穿透曲线解译是一项重要的技术,通过这一技术,可以获得关于地下岩溶管道的信息,如管道的尺寸、连通性、分布和方向等。然而,在实际应用中,仍存在许多问题需要解决,以提高对穿透曲线的解释准确性和可靠性。以平果县平... 详细信息

地下水示踪试验中的穿透曲线解译是一项重要的技术,通过这一技术,可以获得关于地下岩溶管道的信息,如管道的尺寸、连通性、分布和方向等。然而,在实际应用中,仍存在许多问题需要解决,以提高对穿透曲线的解释准确性和可靠性。以平果县平南赤泥堆场地下岩溶系统为例,利用荧光计获取示踪数据结合Qtracer2软件对示踪剂回收率、平均滞留时间、弥散系数、地下水平均流速等参数进行计算,并结合当前被广泛认同的结论对穿透曲线中的多峰、异常波动等现象进行解释。由于本次研究区的岩溶管道规模小,将岩溶管道的复杂性降低到了可计算程度,对并联岩溶管道长度近似值进行计算,最后排除曲线尾部的峰值为溶质暂态存储现象,分析表明研究区属于多管道岩溶系统,地下水主要表现为“岩溶水扩散流”特征。本研究为地下水数值模型提供了依据,为研究如何分析岩溶复杂介质运移特征提供参考。

关键词：示踪试验穿透曲线管道长度暂态存储岩溶

Capacity of FH wireless multi-hop networks

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 78-83页

作者： wei dong-yan WANG wen-bo PENG Mu-gen Key Laboratory of Universal Wireless Communication Ministry of Education Beij hag University of Posts and Telecommunications Beijing 100876 China

In this article,the capacity of wireless multi-hop networks with the frequency hopping（FH） technique is *** from the previous work based on non-spread spectrum（SS） system,this study is based on frequency hopping spread spectrum（FHSS） and the retransmission *** analysis results show that the normalized transport capacity decreases as 1/Mλ,when the total available frequency band is divided into M sub-bands for frequency hopping and the nodes are randomly distributed in space according to a Poisson point process with intensity λ .In this work,the best transmission range per hop to get the maximum capacity is also ***,the results summarize how the capacity of FH wireless multihop networks is affected by the outage probability,target signal to interference plus noise ratio（SINR） and other system parameters.

关键词： multihop frequency hopping capacity

A united tension/compression asymmetry micro-mechanical model for nickel-base single-crystal alloys

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Journal of Iron and Steel Research International 2019年第6期26卷 621-630页

作者： Jian-feng Xiao Hai-tao Cui Hong-jian Zhang wei-dong wen Jiangsu Province Key Laboratory of Aerospace Power System State Key Laboratory of Mechanics and Control of Mechanical Structures College of Energy & Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 Jiangsu China

In recent years, the micro-deformation mechanisms of the tension/compression behavior for nickel-base single-crystal superalloys have been studied extensively and general agreements have been derived. Based on these researches, a new model called united tension/compression asymmetry micro-mechanical model (UTCAM) has been proposed, which can effectively estimate the initial yield strength of nickel-base single-crystal (SC) superalloys under different loading directions. Considering the combined effects of octahedral slip system and cubic slip system, slip control factor is introduced in the UTCAM to determine the type of the open slip system of nickel-base single-crystal superalloys during deformation, thus making this model cover a rather wide range of application. Furthermore, the UTCAM is applied to hot tension and compression tests of three typical nickel-base SC superalloys (PWA1480-593 ℃, RENE N4-760 ℃ and DD407-760 ℃). The predicted initial yield strengths of the nickel-base SC superalloys are in good agreement with the experimental results, and the UTCAM proves to be effective.

关键词： Nickel-base single-crystal superalloy Initial yield strength Tension compression asymmetry Micro/mechanical model

Rabi Oscillations in Two-Component Bose-Einstein Condensates with a Coupling Drive

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Communications in Theoretical Physics 2002年第5期38卷 547-552页

作者： LI wei-dong FAN wen-Bing ZHOU Xiao-Ji WANG Yi-Qiu LIANG Jiu-Qing Department of Physics and Institute of Theoretical Physics Shanxi University Taiyuan 030006 China State Key Lab of Magnetism Institute of Physics the Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Quantum Information and Measurements Ministry of Education of China State Key Lab of Magnetism Institute of Physics the Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Quantum Information and Measurements Ministry of Education of China Department of Electronics Peking University Beijing 100871 China Key Laboratory for Quantum Information and Measurements Ministry of Education of China Department of Electronics Peking University Beijing 100871 China Department of Physics and Institute of Theoretical Physics Shanxi University Taiyuan 030006 China

The Rabi oscillations in two-component Bose-Einstein condensates with a coupling drive are studiedby means of a pair of bosonic operators. The coupling drive and initial phase difference will affect the amplitudeand the period of the Rabi oscillations. The Rabi oscillations will vanish in the evolution of the condensate densityfor some special initial phase differences (ψ = 0 or π). Our theory provides not only an analytical framework forquantitative predictions for two-component condensates, but also gives an intuitive understanding of some mysteriousfeatures observed in experiments and numerical. simulations.

关键词： Bose-Einstein condensates, R.abi oscillations

Evaluation of dry eye disease symptomatology and mental health status among patients with different COVID-19 statuses

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 822-830页

作者： Fang Ruan wen-Jun Kong Qian Fan Hong-wei dong wei Zhang wen-Bin wei Ying Jie Department of Ophthalmology Beijing You’an HospitalCapital Medical UniversityBeijing Infectious Eye Disease Diagnosis and Treatment CenterBeijing 100069China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Institute of OphthalmologyBeijing Ophthalmology and Visual Sciences Key LabBeijing 100730China Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteNankai University Affiliated Eye HospitalNankai University Eye InstituteNankai UniversityClinical College of OphthalmologyTianjin Medical UniversityTianjin 300020China

AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 ***:A cross-sectional observational design was *** 123 eligible adults(46.34%of men,age range,18-59y)with COVID-19 included in the study from August to November,*** Surface Disease Index(OSDI),Five-item Dry Eye Questionnaire(DEQ-5),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI)were used in this ***:OSDI scores were 6.82(1.25,15.91)in asymptomatic carriers,7.35(2.50,18.38)in mild cases,and 16.67(4.43,28.04)in recurrent cases,with 30.00%,35.56%,and 57.89%,respectively evaluated as having DED symptoms(χ2=7.049,P=0.029).DEQ-5 score varied from 2.00(0,6.00)in asymptomatic carriers,3.00(0,8.00)in mild cases,and 8.00(5.00,10.00)in recurrent cases,with 27.50%,33.33%,and 55.26%,respectively assessed as having DED symptoms(χ2=8.532,P=0.014).The prevalence of clinical anxiety(50.00%)and depression(47.37%)symptoms were also significantly higher in patients with recurrent infection(χ2=24.541,P<0.001;χ2=30.871,P<0.001).Recurrent infection was a risk factor for high OSDI scores[odds ratio,2.562;95%confidence interval(CI),1.631-7.979;P=0.033]and DEQ-5 scores(odds ratio,3.353;95%CI,1.038-8.834;P=0.043),whereas having a fixed occupation was a protective factor for OSDI scores(odds ratio,0.088;95%CI,0.022-0.360;P=0.001)and DEQ-5 scores(odds ratio,0.126;95%CI,0.039-0.405;P=0.001).CONCLUSION:Patients with recurrent COVID-19 have more severe symptoms of DED,anxiety,and depression.

关键词： COVID-19 dry eye disease recurrent infection mental health

A semi-analytical model for coupled flow in stress-sensitive multi-scale shale reservoirs with fractal characteristics

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Petroleum Science 2024年第1期21卷 327-342页

作者： Qian Zhang wen-dong Wang Yu-Liang Su wei Chen Zheng-dong Lei Lei Li Yong-Mao Hao Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Oil Development Branch Changqing Oilfield CompanyPetroChinaQingyang745708GansuChina PetroChina Research Institute of Petroleum Exploration&Development Beijing100083China

A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation.

关键词： Multi-scale coupled flow Stress sensitivity Shale oil Micro-scale effect Fractal theory

Observation of gapless corner modes of photonic crystal slabs in synthetic translation dimensions

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Photonics Research 2024年第3期12卷 444-455页

作者： wen-JIN ZHANG HAO-CHANG MO wen-JIE CHEN XIAO-dong CHEN JIAN-wen dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Second-order topological photonic crystals support localized corner modes that deviate from the conventional bulk-edge ***,the frequency shift of corner modes spanning the photonic band gap has not been experimentally ***,we observe the gapless corner modes of photonic crystal slabs within a parameter space by considering translation as an additional synthetic *** corner modes,protected by topological pumping in synthetic translation dimensions,are found to exist independently of the specific corner *** gapless corner modes are experimentally imaged via the near-field scanning measurement and validated numerically by full-wave *** propose a topological rainbow with gradient translation,demonstrating the ability to extract and separate specific frequency components of light into different spatial *** work contributes to the advancement of topological photonics and provides valuable insights into the exploration of gapless corner modes in synthetic dimensions.

关键词： translation dimensions corner

State of the art of lightweight aggregates used in lightweight refractories for working lining of high-temperature furnaces

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Journal of Iron and Steel Research International 2024年第6期31卷 1320-1343页

作者： wei Zhang wen-yong Dai Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Research and Development Department AGC Plibrico(Dalian)Industries Inc.Dalian 116600LiaoningChina

Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and *** prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the ***,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread *** available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based ***,the future development trend of lightweight aggregates was proposed.

关键词： Lightweight aggregate Lightweight refractory Working lining Apparent porosity Closed porosity Thermal conductivity Pore-forming approach

In situ synthesis of porous Pt-Pd bimetallic structures for sweat glucose biosensing using dynamic hydrogen bubble template method

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Rare Metals 2024年第7期43卷 3408-3414页

作者： Yi-wen Guo Qian-Hui wei Fei wei Hao Liu Hong-Bin Zhao dong Wang Hai-Ling Tu State Key Laboratory of Advanced Materials for Smart Sensing China GRINM Group Co.Ltd.Beijing 100088China Department of Advanced Electronic Materials GRIMAT Engineering Institute Co.Ltd.Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China GRINM(Guangdong)Institute for Advanced Materials and Technology Foshan 528000China School of Chemical Engineering Northeast Electric Power UniversityJilin 132012China

For the practical application of sweat glucose biosensors,it is crucial to develop a method for modifying the working electrode with noble metals that ensures strong *** this study,we synthesized porous Pt-Pd bimetall... 详细信息

关键词： method bubble porous