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Diagnosis of deformation-derived ascending areas in a rainband

Atmospheric and Oceanic Science Letters 2018年第4期11卷 300-306页

作者： LI Na ran ling-kun GAO Shou-Ting Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Plateau Atmosphere and Environment Key Laboratory of Sichuan Province SichuanChina

This paper demonstrates that,for a moist baroclinic frontal system,the large-value deformation belt in the low-level atmosphere overlaps with *** precisely describe the relationship between deformation and heavy precipitation,deformation is introduced into the nongeostrophic Q^#-vector.Q^#is then decomposed into three parts:the divergence-related term,the vorticity-related term,and the deformation-related *** calculating the divergence of Q#and its components,it is found that in strong ascending areas within precipitation regions the nongeostrophic Q^#-vector divergence shows strong negative *** deformational component can contribute about 68%to these negative *** verifies that strong deformation in a precipitating atmosphere is favorable for the development of convection and *** addition,by calculating the correlation coefficients between the Q^#-vector(including its components)divergence and vertical motions,it is also found that the Q^#-vector divergence shows higher correlation with vertical motion within the precipitation belt and lower correlation in the non-precipitation areas,which indicates a larger contribution of Q^#to vertical motion when precipitation occurs and implies an effect of Q^#to the precipitation distribution or spatial *** the three components of the Q^#-vector,the correlation coefficients between the deformational component and vertical motion are the most similar in pattern to that of the correlation coefficients between the Q#-vector and vertical motion,which further reflects the important contribution of deformation to the large spatial variability of precipitation.

关键词： Deformation Q-vector precipitation ascending motion

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Influence of Mass and Radius of Ice Crystals on Hydrometeors,Internal Energy,and Kinetic Energy:A Numeric Model Study

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Atmospheric and Oceanic Science Letters 2014年第1期7卷 49-55页

作者： ran ling-kun QI Yan-Bin LI Na Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of Sciences Jilin Weather Modification Office University of Chinese Academy of Sciences

Two cloud-scale experiments with two different ice-phase schemes were carried out for a precipitation event that occurred in eastern China in *** results were analyzed to examine the influences of the change of ice-particle mass and radius on hydrometeors,internal energy,and kinetic energy,as well as the primary factors *** was found that the ice content increases notably and the snow content decreases due to the *** is the consequence of the modulation of cloud microphysical *** particular,the Bergeron process and the accretion of snow and cloud ice are markedly *** differences of internal energy and kinetic energy between the two experiments are caused by adjustments to pressure-flux divergence,the coupling of temperature and divergence,and gravitational work,and the reason is that these three factors result in differences of local changes of internal and kinetic energy.

关键词： mass and radius of ice crystals cloud hydrometeors internal energy kinetic energy

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Analysis of Pseudomomentum Wave-Activity Density in a Heavy Rainfall Event in East China

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Atmospheric and Oceanic Science Letters 2014年第1期7卷 42-48页

作者： ran ling-kun HAO Shou-Chang QI Yan-Bin Institute of Atmospheric Physics Chinese Academy of Sciences Shanxi Provincial Meteorological Service Weather Modification Center Chinese Academy of Meteorological Sciences

Taking into account moisture in virtue of general potential temperature,the author derive a three-dimensional(3D) pseudomomentum wave-activity relation for the moist atmosphere from the primitive equations in Cartesian coordinates using the Momentum-Casimir *** the wave-activity relation is constructed in an ageostrophic and non-hydrostatic dynamical framework,it may be applicable to diagnosing the evolution and propagation of mesoscale systems leading to heavy *** theoretical analysis shows that,besides the local change of wave-activity flux divergence and source or sink,the wave-activity relation includes two additional forcing *** first is the zonal gradient of difference between general potential temperature and potential temperature perturbations,and the second is the covariance of the solenoid and gradient of water vapor,denoting the direct influence of moisture on wave-activity *** wave-activity density was applied to a heavy precipitation event occurring in the Jianghuai region of *** calculation showed that the wave-activity density was consistent with 6-h accumulated precipitation observations,in terms of both spatial distribution and temporal *** suggested that the disturbance represented by wave-activity density was closely related to the heavy *** the wave-activity flux divergence and the covariance of the solenoid and gradient of water vapor made the primary contribution to the local change of wave-activity density,the covariance was more *** zonal gradient of difference between general potential temperature and potential temperature perturbations made a weaker contribution to the waveactivity density.

关键词： pseudomomentum wave-activity density wave-activity flux wave-basic flow interaction heavy precipitation event

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平流涡度方程及其在2006年Bilis台风分析中的应用

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物理学报 2010年第2期59卷 1366-1377页

作者：周玉淑冉令坤中国科学院大气物理研究所北京100029

推导得到气压坐标中的动量叉乘形式的垂直涡度方程,这个动量叉乘形式的涡度方程包含了水平风的平流旋转效应,可称为平流涡度方程.由于水平风场的平流作用可由等压面天气图直观分析得到,因此平流涡度方程可方便用于实际天气分析.对2006年... 详细信息

推导得到气压坐标中的动量叉乘形式的垂直涡度方程,这个动量叉乘形式的涡度方程包含了水平风的平流旋转效应,可称为平流涡度方程.由于水平风场的平流作用可由等压面天气图直观分析得到,因此平流涡度方程可方便用于实际天气分析.对2006年的Bilis台风移动过程中由经典涡度方程和平流涡度方程计算得到的垂直涡度倾向进行对比分析发现,二者计算得到的垂直涡度倾向变化的分布形式接近,但平流涡度方程计算得到的倾向的数值明显大于经典涡度方程的数值,正负涡度倾向区也更集中.对Bilis移动过程中的垂直涡度方程和平流涡度方程中各项的计算分析表明,水平风场的平流旋转作用是Bilis发展移动过程中垂直涡度变化的一个主要因素,是造成垂直涡度增强并发展的主要原因.因此,当水平风场平流旋转效应较强时,平流作用对垂直涡度倾向变化起主导作用,可直接用平流项来近似分析Bilis台风的涡度变化.而平流涡度方程中地转涡度和散度项的变化趋势与Bilis台风的移动路径有较好的一致性,这一项对台风的移动路径预报有更好的指示意义.

关键词：平流作用涡度方程台风

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In-situ TEM study of the effect of hydrogen-helium ratio on defect characteristics in Fe9Cr1.5W0.4Si F/M steel during H_(2)^(+)&He^(+)simultaneous irradiation

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Journal of Materials Science & Technology 2024年第6期173卷 192-201页

作者： Dewang Cui Ziqi Cao kun He Yuanming Li Xi Qiu Guang ran College of Energy Xiamen UniversityXiamen 361102China Fujian Provincial Nuclear Energy Engineering Technology Research Center Xiamen 361102China Science and Technology on Reactor Fuel and Materials Laboratory Chengdu 610041China Nuclear Power Institute of China Chengdu 610041China Science and Technology on Reactor System Design Technology Laboratory Chengdu 610041China

The effect of hydrogen and helium interaction,especially H-He ratio,on the irradiation behavior of nuclear materials has not yet been ***,this is an important basis for evaluating the irradiation properties of nuclear materials and developing high irradiation resistant ***,30 keV H_(2)^(+)and He^(+)dual beams with four H-He ratios of 0:10,3:10,15:10,and 30:10 were used to irradiate the newly developed Fe9Cr1.5W0.4Si F/M steel in TEM to in-situ study the interaction and ratio effect of hydrogen and *** addition of H atoms significantly promoted the nucleation of dislocation loops and *** the early stage of irradiation,the average size and density of dislocation loops increased with the increase of H-He ***,the larger the H-He ratio,the easier it was to form a complex dislocation ***,the final saturation size of bubbles increased with the increase of H-He *** was first found that the swelling was affected by H concentrations,with high H concentrations slowing down the increase in *** a certain irradiation dose,a specific H-He ratio would lead to a swelling peak of Fe9Cr1.5W0.4Si F/M *** super-sized bubbles at grain boundaries(GBs)were found after H addition,resulting in a bigger swelling of GBs than the *** the swelling of the GBs and the matrix show a dependence on the H-He *** current work is of great significance for understanding the interaction between hydrogen and helium in nuclear materials.

关键词： Dose ratio effect Ferritic-martensitic steel Hydrogen&helium synergetic irradiation In-situ TEM

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Editable semiconductor photo-electrodes for sustainable ammonia synthesis

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Nano Research 2024年第4期17卷 3107-3112页

作者： Ning Lan kun Du Erling Zhao Wei Zhao Tao ling Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Institute of New-EnergySchool of Materials Science and EngineeringTianjin UniversityTianjin 300072China School of Materials Science and Engineering Tianjin Chengjian UniversityTianjin 300384China

Powered by an inexhaustible supply of solar energy,photoelectrochemical(PEC)nitrogen reduction reaction(NRR)provides an ideal solution for the synthesis of green ammonia(NH_(3)).Although great efforts have been made in the past decades,there are still significant challenges in increasing the NH_(3) yields of the PEC-NRR *** addition to the issues of low activity and selectivity similar to electrochemical NRR,the progress of PEC-NRR is also impeded by the limited increase in NH_(3) yields as the electrode is ***,we propose an editable electrode design strategy that parallels unit photo-electrodes to achieve a linear increase in NH_(3) yields with electrode active *** demonstrate that the editable electrode design strategy minimizes the electrode charge transfer resistance,allowing more photo-generated carriers to reach the electrode surface and promote the catalytic *** believe that this editable electrode design strategy provides an avenue to achieve sustainable PEC NH_(3) production.

关键词： editable electrode photoelectrochemical nitrogen reduction reaction parallel electrode ZnSe

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Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3071-3088页

作者： Chun-Ming Wu Jin Lei Wu-Kai Liu Mei-ling Ren ling-Li ran Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology School of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Biomedical Engineering Taiyuan University of TechnologyTaiyuan030600China

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model *** algorithm is validated in detail on two vessel *** comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance ***,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO ***,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

关键词： Unmanned ships R_YOLO EMA CSPStage YOLOv8s

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台风暴雨过程中位势散度波作用密度分析和预报应用研究

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地球物理学报 2013年第10期56卷 3285-3301页

作者：冉令坤刘璐李娜齐彦斌中国科学院大气物理研究所中国科学院研究生院吉林省人工影响天气办公室

在位涡的基础上,考虑散度效应,把水平风矢量旋转90°后的旋度在广义位温梯度方向上的投影定义为位势散度,并把其二阶扰动量定义为位势散度波作用密度,该波作用密度代表扰动热量的扰动输送,与位势稳定度的发展演变有关.登陆台风Morakot(2... 详细信息

在位涡的基础上,考虑散度效应,把水平风矢量旋转90°后的旋度在广义位温梯度方向上的投影定义为位势散度,并把其二阶扰动量定义为位势散度波作用密度,该波作用密度代表扰动热量的扰动输送,与位势稳定度的发展演变有关.登陆台风Morakot(2009)的诊断分析表明,在台风登陆台湾岛,进入台湾海峡和登陆大陆三个阶段,波作用密度高值区与大陆和台湾降水区相重叠,扰动热量的扰动输送显著;在前两个阶段,大陆和台湾降水区波作用密度逐渐增大,扰动热量的扰动输送逐步增强;在台风登陆福建霞浦市后,大陆地区波作用密度减小,扰动热量的扰动输送减弱.在影响波作用密度局地变化的诸多物理因素中,扰动非地转风位涡项是主要强迫项.统计分析表明,波作用密度与观测降水有一定的相关性,据此发展了位势散度波作用密度降水预报方程,其本质是数值模式预报资料的动力延伸释用,预报应用表明,利用24h模式预报场计算的波作用密度降水能够较好地再现观测降水的落区,对台风Morakot引发的暴雨有一定的预报技巧.

关键词：位涡位势散度波作用密度波作用通量散度

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Phosphotungstic acid immobilized on amino-functionalized TS-1 zeolite as a solid acid catalyst for the synthesis of tributyl citrate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 199-210页

作者： Pei Li Bianfang Shi Junyao Shen ran Cui Wenze Guo ling Zhao Zhenhao Xi State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic *** Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the *** amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid *** tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid *** optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized *** catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.

关键词： Amino-functionalization Phosphotungstic acid TS-1 zeolite Esterification Tributyl citrate

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Nab-paclitaxel plus capecitabine as first-line treatment for advanced biliary tract cancers:An open-label,non-randomized,phase II clinical trial

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World Journal of Gastroenterology 2024年第30期30卷 3564-3573页

作者： ling-Xiao Xu Jia-Jia Yuan ran Xue Jun Zhou Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)Peking University Cancer Hospital and InstituteBeijing 100142China

BACKGROUND Biliary tract cancers(BTCs)are a heterogeneous group of tumors with high malignancy,poor prognosis,and limited treatment *** To explore the efficacy and safety of nab-paclitaxel plus capecitabine as first-line treatment for advanced and metastatic *** This open-label,non-randomized,double-center,phase II clinical trial recruited systemic therapy-naive patients with unresectable or metastatic BTCs between April 2019 and June 2022 at Beijing Cancer Hospital and the First Hospital of China Medical *** patients were administered nab-paclitaxel(150 mg/m^(2),day 1)and capecitabine(2000 mg/m^(2),twice daily,days 1-7)in 14-day cycles until experiencing intolerable toxicity or disease *** primary outcome was the objective response rate(ORR).The secondary outcomes included the disease control rate(DCR),overall survival(OS),progression-free survival(PFS),and *** A total of 44 patients successfully completed the trial,with a median age of 64.00 years(interquartile range,35.00-76.00),and 26(59.09%)were *** response assessment was impeded for one patient due to premature demise from tumor *** the remaining 43 patients undergoing at least one imaging assessment,the ORR was 23.26%[95%confidence interval(CI):11.80%-38.60%],and the DCR was 69.77%(95%CI:53.90%-82.80%).The median OS was 14.1 months(95%CI:8.3-19.9),and the median PFS was 4.4 months(95%CI:2.5-6.3).A total of 41 patients(93.18%)experienced at least one adverse event(AE),with 10 patients(22.73%)encountering grade≥3 AEs,and the most frequent AEs of any grade were alopecia(79.50%),leukopenia(54.55%),neutropenia(52.27%),and liver dysfunction(40.91%),and no treatment-related deaths were *** Nab-paclitaxel plus capecitabine may be an effective and safe first-line treatment strategy for patients with advanced or metastatic BTCs.

关键词： Nab-paclitaxel Capecitabine Biliary tract cancer Objective response rate Phase II clinical trial

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