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Flow regime and energy dissipation of SFS-type flip buckets

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Journal of Hydrodynamics 2020年第1期32卷 179-182页

作者： ran tian Jian-hua Wu Fei Ma College of Water Conservancy and Hydropower Engineering.Hohai University Nanjing 210098China

In the present work,a slot-type flip bucket with separated flows,called SFS-type flip bucket,is developed,and flow regime and energy dissipation are experimentally *** with the circular-shaped or slot-type flip bucket buckets,the present SFS-type flip bucket has better flow regime and larger energy dissipation since the three branches of the flows are separated through the outlet of the flip ***,the energy dissipation for this flip bucket is estimated.

关键词： Energy dissipation flow region separated flow SFS-type flip bucket

Flow characteristics of tangential leakage in a scroll compressor for automobile heat pump with CO_(2)

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Science China(Technological Sciences) 2021年第5期64卷 971-983页

作者： ZHENG SiYu WEI MingShan HU ChenXing SONG PanPan tian ran School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Tangential leakage loss reduction has great significance on improving the performance of scroll *** this study,the flow field of a scroll compressor working with CO_(2) was numerically *** development characteristics of the tangential leakage flow in different working chambers were carried out,which was obtained by analyzing the field quantities *** impacts of the radial clearances and sidewall roughness on the tangential leakage were also taken into consideration,in order to explore the feasible method of the flow control for the tangential leakage in scroll *** showed that the tangential leakage flow had various characteristics in the suction and compression chambers due to the different interactions between the tangential leakage flow and *** to little reverse pressure gradient,the tangential leakage flow maintained the typical jet form in the suction *** contrast,the mixing of the tangential leakage flow and mainstream induced the passage vortex and secondary flows in the compression *** secondary flow was the primary factor that results in the occurrence of localized high temperature region rather than the tangential *** the increase of the radial clearance,the volumetric efficiency declined and the discharge temperature increased *** terms of flow control of the tangential leakage,the increase of sidewall roughness by 2μm could achieve the same effect as the decrease of the radial clearance by 4μm,while the volumetric efficiency increased by almost 5%and average discharge temperature decreased by 5K.

关键词： carbon dioxide scroll compressor field synergy principle tangential leakage sidewall roughness

Synthesis of 3-Phenyl-6-formyl-3, 4-dihydro-2H-1, 3-benzoxazine

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Chinese Chemical Letters 2006年第10期17卷 1305-1308页

作者： Qi Chao ran Qiao tian Yi GU State Key Laboratory of Polymeric Materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065

A novel benzoxazine monomer containing aldehyde group, 3-phenyl-6-formyl-3, 4-dihydro-2H-1, 3-benzoxazine （Ald-B）, was synthesized via the Mannich condensation of formaldehyde, p-hydroxybenzaldehyde and aniline. Its structure was characterized by Fourier transform infrared spectroscopy （FTIR）, proton nuclear magnetic resonance （^1HNMR）. The side reaction in the synthesis is discussed.

关键词： Benzoxazine aldehyde group synthesis Schiff base.

Home location inference from sparse and noisy data:models and applications

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Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 389-402页

作者： tian-ran HU Jie-bo LUO Henry KAUTZ Adam SADILEK Computer Science Department University of Rochester

Accurate home location is increasingly important for urban computing. Existing methods either rely on continuous(and expensive) Global Positioning System(GPS) data or suffer from poor accuracy. In particular, the sparse and noisy nature of social media data poses serious challenges in pinpointing where people live at scale. We revisit this research topic and infer home location within 100 m×100 m squares at 70% accuracy for 76% and 71%of active users in New York City and the Bay Area, respectively. To the best of our knowledge, this is the first time home location has been detected at such a fine granularity using sparse and noisy data. Since people spend a large portion of their time at home, our model enables novel applications. As an example, we focus on modeling people's health at scale by linking their home locations with publicly available statistics, such as education disparity. Results in multiple geographic regions demonstrate both the effectiveness and added value of our home localization method and reveal insights that eluded earlier studies. In addition, we are able to discover the real buzz in the communities where people live.

关键词： Home location Mobility patterns Healthcare

Mean-field type FBSDEs in a domination-monotonicity framework and LQ multi-level Stackelberg games

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Probability, Uncertainty and Quantitative Risk 2022年第3期7卷 215-246页

作者： ran tian Zhiyong Yu Zhongtai Securities Institute for Financial Studies Shandong UniversityJinan 250100China School of Mathematics Shandong UniversityJinan 250100China

Motivated by various mean-field type linear-quadratic(MF-LQ,for short)multilevel Stackelberg games,we propose a kind of multi-level self-similar randomized dominationmonotonicity *** the coefficients of a class of mean-field type forwardbackward stochastic differential equations(MF-FBSDEs,for short)satisfy this kind of structures,we prove the existence,the uniqueness,an estimate and the continuous dependence on the coefficients of ***,the theoretical results are applied to construct unique Stackelberg equilibria for forward and backward MF-LQ multi-level Stackelberg games,respectively.

关键词： Forward-backward stochastic differential equation Stochastic linearquadratic problem Stackelberg stochastic differential game Mean-field Stochastic optimal control

Tight oil accumulation of the redeposited carbonates in the continental rift basin:A case study from Member 3 of Shahejie Formation in Shulu sag of Jizhong depression,North China

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Petroleum Research 2017年第1期2卷 77-89页

作者： Jianzhang tian ran tian Kaiyan Chen Shuguang Chen Zengqiang Guo Geophysical Exploration Research Institute PetroChina Huabei Oilfield CompanyHebei 062552China Exploration and Development Research Institute PetroChina Huabei Oilfield CompanyHebei 062552China

Tight oil in the redeposited carbonates was mainly distributed in the Lower Submember of Member 3 of Shahejie Formation in Shulu sag of Jizhong depression,North *** high-resolution 3D seismic data,well logging data and drilling data,the Lower Submember of Member 3 of Shahejie Formation was divided into 5 third-order sequences and 15 parasequence *** redeposited marl and rudstone were major reserving horizons of tight oil,and ten reserving space types were developed and could be classified into two main categories,i.e.,pores and *** types of tight oil reservoirs were established,i.e.,the marl hydrocarbon reservoir of the source-reservoir integration and the rudstone hydrocarbon reservoirs of the source-reservoir *** assemblage relationship among the high-quality source rocks,system tracts with the source-reservoir configuration was the major control factor for tight oil accumulation in the redeposited *** lacustrine transgressive system tracts and highstand systems tracts in SQ1 to SQ5 were the favorable horizons for development of the marl hydrocarbon reservoir,the lowstand system tracts in SQ1 to SQ3 were the favorable horizons for development of the rudstone hydrocarbon reservoir.

关键词： Member 3 of Shahejie Formation Tight oil Re-deposited carbonate Marl Rudstone Third-order sequence Hydrocarbon reservoir

Magnetic Resonance Urography and X-ray Urography Findings of Congenital Megaureter

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Chinese Medical Sciences Journal 2011年第2期26卷 103-108页

作者： tian-ran Li Xiang-ke Du tian-long Huo Department of Radiology Peking University People＇s Hospital Beijing 100044 China

Objective To observe the imaging findings of congenital megaureter in order to enhance the understanding of this disease. Methods Image data of 5 patients with congenital megaureter and 2 misdiagnosed patients were analyzed, and image findings of congenital megaureter were summarized. Elscint Prestig 2.0T superconductive magnetic resonance urography （MRLI） with conventional sequence （spin-echo, T 1W1560 ms/16 ms; fast spin-echo, T2WI 9600 ms/96 ms） was performed. Raw data were acquired with fast spin-echo sequence from heavy T2-weighted image （9600 ms/120 ms）. Post-processing method of MRH was the maximum in- tensity projection with three-dimensional reconstruction in the workstation. Intravenous pyelography （IVP） was conducted, in which X-ray films were taken 7 minutes, 15 minutes, and 30 minutes after injecting contrast agent, except that in 2 patients the films were taken delayed at 60 and 90 minutes. X-ray retrograde pyelography was performed on 2 patients, successful in one but failed in the other. Results The dilated ureter showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in conventional MRI. The mass wall was intact, uniform in thickness, and showing hy- pointensity on Tl-weighted and T2-weighted images. The MRH images showed a retroperitoneal mass appearing as an elongated tubular cystic structure spreading from kidney to bladder. MRLI also revealed dilated calices and renal pelvis, pelviureteric obstruction, and renal duplication. The main signs of congenital megaureter in X-urography was significant dilatation of ureter, or normal renal pelvis with ureter dilatation, hydronephrosis, deformity, and displacement. Conclusions MRH with X-urography could visualize the characteristics of congenital megaureter, including the dilation of renal pelvis and ureter, calculi, urinary tract duplication, and stenosis location. The two techniques can complement each other in disease diagnosis and provide more detailed information for

关键词： congenital megaureter magnetic resonance urography intravenous pyelo-graphy

Acute systemic accumulation of acrolein in mice by inhalation at a concentration similar to that in cigarette smoke

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Neuroscience Bulletin 2014年第6期30卷 1017-1024页

作者： Melissa Tully Lingxing Zheng Glen Acosta ran tian Riyi Shi Weldon School of Biomedical Engineering Purdue UniversityWest LafayetteINUSA Indiana University School of Medicine IndianapolisINUSA Department of Basic Medical Sciences College of Veterinary MedicinePurdue UniversityWest LafayetteINUSA

Cigarette smoke is an important environmental factor associated with a wide array of public health concerns. Acrolein, a component of tobacco smoke and a known toxin to various cell types, may be a key pathological factor mediating the adverse effects linked with tobacco smoke. Although acrolein is known to accumulate in the respiratory system after acute nasal exposure, it is not clear if it accumulates systemically, and less is known in the nervous system. The aim of this study was to assess the degree of acrolein accumulation in the circulation and in the spinal cord following acute acrolein inhalation in mice. Using a laboratory-fabricated inhalation chamber, we found elevated urinary 3-HPMA, an acrolein metabolite, and increased acrolein adducts in the spinal cord after weeks of nasal exposure to acrolein at a concentration similar to that in tobacco smoke. The data indicated that acrolein is absorbed into the circulatory system and some enters the nervous system. It is expected that these findings may facilitate further studies to probe the pathological role of acrolein in the nervous system resulting from smoke and other external sources.

关键词： tobacco lipid peroxidation urine liquid chromatography mass spectrometry

Formation conditions and reservoir-forming models of the Ordovician buried hill reservoirs in the Jizhong depression

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地学前缘 2023年第1期30卷 229-241页

作者： ZHANG Ruifeng tian Jianzhang HUANG Yuanxin tian ran REN Yi BIAN Yingying WANG Yuanjie CHEN Ling LU Shan PetroChina Huabei Oilfield Company Renqiu 062552China Exploration and Development Research Institute of PetroChina Huabei Oilfield Company Renqiu 062552China

The buried hill in the Jizhong depression contains abundant petroleum reserves and are important production *** Ordovician buried hill has restricted the discovery of new oil and gas exploration targets because of its strong reservoir heterogeneity and complex reservoir-controlling *** on a large volume of core,thin section,logging,seismic,and geochemical data and numerous geological analyses,the reservoir-forming conditions and modes were systematically analyzed to guide the exploration and achieve important breakthroughs in the Yangshuiwu and Wen an slope buried *** study revealed that three sets of source rocks of the third and fourth members of the Shahejie Formation from the Paleogene and Carboniferous-Permian were developed in the Jizhong depression,providing sufficient material basis for the formation of buried hill oil and gas *** reservoir control mechanism involving the three major factors of“cloud-karst-fault”was clarified,and karst cave,fracture fissure-pore,and cloud pore type reservoir models were established,thereby expanding the exploration *** by the superposition of multi-stage tectonic processes during the Indosinian,Yanshanian,and Himalayan,two genetic buried hill trap types of uplift-depression and depression-uplift were *** on the analysis of reservoir-forming factors of the Ordovician buried hill,three buried hill oil and gas reservoir-forming models were identified:low-level tectonic-lithologic composite quasi-layered buried hill,medium-level paleo-storage paleo-block buried hill,and high-level paleo-storage new-block buried *** evaluations indicate that the reservoir-forming conditions of the low-level tectonic-lithologic composite quasi-layered buried hill in the northern portion of the Jizhong depression are the most favorable and that the Sicundian and Xinzhen buried hills are favorable areas for future exploration.

关键词： Jizhong depression Yangshuiwu Ordovician reservoir type reservoir model