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The applicability of vortex identification methods for complex vortex structures in axial turbine rotor passages

Journal of Hydrodynamics 2019年第4期31卷 700-707页

作者： Yu-fan Wang wei-hao zhang Xia Cao Hong-kai Yang National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beihang University Beijing 100191 China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191 China

The complex vortex structures in the flow around turbine rotor passages, with weak or strong, large or small vortices, interacting with each other, often generate most of aerodynamic loss in turbomachines. Therefore, it is important to identify the vortex structures accurately for the flow field analysis and the aerodynamic performance optimization for turbomachines. In this paper, by using 4 vortex identification methods (the Q criterion, the Q method, the Liutex method and the Q -Liutex method), the vortices are identified in turbine rotor passages. In terms of the threshold selection, the results show that the D method and the Q -Liutex method are more robust, by which strong and weak vortices can be visualized simultaneously over a wide range of thresholds. As for the display consistency of the vortex identification methods and the streamlines, it is shown that the Liutex method gives results coinciding best with the streamlines in identifying strong vortices, while the Q -Liutex method gives results the most consistent with the streamlines in identifying weak vortices. As to the relationship among the loss, the vortices and the shear, except for the Q criterion, the other three methods can distinguish the vortical regions from the high shear regions. And the flow losses in turbine rotor passages are often related to high shear zones, while there is a small loss within the core of the vortex. In order to obtain the variation of vortices in the turbine rotor passages at different working points, the Liutex method is applied in 2 cases of a turbine with different angles of attack. The identification results show that the strengths of the tip leakage vortex and the upper passage vortex are weaker and the distance between them is closer at a negative angle of attack. This indicates that the Liutex method is an effective method, and can be used to analyze the vortex structures and their evolution in turbine rotor passages.

关键词： Vortex identification tip leakage vortex turbine rotor passage Liutex method Q -Liutex method

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Estimating stellar effective temperatures and detected angular parameters using stochastic particle swarm optimization

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Research in Astronomy and Astrophysics 2016年第9期16卷 65-74页

作者： Chuan-Xin zhang Yuan Yuan hao-wei zhang Yong Shuai He-Ping Tan School of Energy Science and Engineering Harbin Institute of Technology

Considering features of stellar spectral radiation and sky surveys, we established a computational model for stellar effective temperatures, detected angular parameters and gray rates. Using known stellar flux data in some bands, we estimated stellar effective temperatures and detected angular parameters using stochastic particle swarm optimization （SPSO）. We first verified the reliability of SPSO, and then determined reasonable parameters that produced highly accurate estimates under certain gray deviation levels. Finally, we calculated 177 860 stellar effective temperatures and detected angular parameters using data from the Midcourse Space Experiment （MSX） catalog. These derived stellar effective temperatures were accurate when we compared them to known values from literatures. This research makes full use of catalog data and presents an original technique for studying stellar characteristics. It proposes a novel method for calculating stellar effective temperatures and detecting angular parameters, and provides theoretical and practical data for finding information about radiation in any band.

关键词： physical data and process radiative transfer -- methods data analysis -- astronomical databases miscellaneous -- stars atmospheres

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Study on the Programming Standard for Ecological Rescue in General Land Use Planning

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Chinese Journal of Population,Resources and Environment 2006年第4期4卷 43-47页

作者： Bai wei hao Jinmin zhang Qiuping Department of Land Resource Management China Agricultural University Beijing 100094 China Department of Land Resource Management China Agricultural University Beijing 100094 China Department of Land Resource Management China Agricultural University Beijing 100094 China

This paper aims at establishing the operation idea based on the analysis of the connotation,principles and reference indexes for programming standard for ecological *** paper puts forward that the programming standard should take into account the natural,social and economic reference indexes,and modifies the scale and distribution of the ecological rescue according to the order of ecological safety,social safety and economic *** paper suggests that the land planning department should strengthen the study and datum accumulation in order to establish the technology regulations of programming standard of the ecological rescue.

关键词： land use planning idea sum up ecological rescue programming standard

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Comprehensive recovery of lead, zinc, and iron from hazardous jarosite residues using direct reduction followed by magnetic separation

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 123-130页

作者： Ya-yun Wang Hui-fen Yang Bo Jiang Rong-long Song wei-hao zhang Key Laboratory for High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology Beijing School of Civil and Resource Engineering University of Science and Technology Beijing

Lead, zinc, and iron were recovered from jarosite residues using direct reduction followed by magnetic separation. The influence of the coal dosage, reduction temperature, and reduction time on the volatilization rates of lead and zinc and the metallization rate of iron were investigated. The results show that the volatilization rates of lead and zinc were 96.97% and 99.89%, respectively, and the iron metallization rate was 91.97% under the optimal reduction roasting conditions of a coal dosage of 25.0 wt% and reduction roasting at 1250°C for 60 min. The magnetic concentrate with an iron content of 90.59 wt% and an iron recovery rate of 50.87% was obtained under the optimum conditions in which 96.56% of the reduction product particles were smaller than 37 μm and the magnetic field strength was 24 k A/m. Therefore, the results of this study demonstrate that recovering valuable metals such as lead, zinc, and iron from jarosite residues is feasible using the developed approach.

关键词： jarosite residues recovery direct reduction magnetic separation valuable metals

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Giant low-grade appendiceal mucinous neoplasm: A case report

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World Journal of Clinical Cases 2019年第13期7卷 1726-1731页

作者： Jian-Ming Yang wei-hao zhang Dan-Dan Yang hao Jiang Lei Yu Feng Gao Department of Colorectal Cancer Surgery Second Affiliated Hospital of Harbin Medical University

BACKGROUND Appendiceal mucinous neoplasm (AMN) is extremely rare. Since the disease does not manifest a characteristic profile of clinical symptoms, it is easy to misdiagnose and still difficult to diagnose without operation. Here, we report a case of low-grade AMN (LAMN) and summarize its clinical features, diagnosis, and treatment. CASE SUMMARY A 63-year-old postmenopausal woman presented with a history of right lower abdominal mass. The patient underwent laparotomy, which showed an appendiceal mucocele originating from the apex of the appendix, and a simple appendectomy was performed. The subsequent histological assessment identified an LAMN with no lymph node involvement and negative surgical margin. The patient received six cycles of chemotherapy after surgery, and to date, more than a year after the surgery, the patient remains in good health. CONCLUSION A unified, standardized, detailed, and accurate pathological diagnosis is needed for LAMN, to facilitate selection of an appropriate surgical plan. In addition, the surgeon should record the details of the tumors in the surgical records in order to facilitate follow-up after surgery.

关键词： Mucocele of appendix Appendiceal mucinous neoplasm Low-grade appendiceal mucinous neoplasm Pathological profile Diagnosis Case report

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Assessment of natural resources and the policy of subsidies in grain production

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Ecological Economy 2006年第1期2卷 42-46页

作者： Bai wei hao Jinmin zhang Qiuping College of Resources and Environment China Agricultural University Beijing 100094 P R. China

Based on the analysis on the status quo of natural resources input in Brain production and on the policy of Brain subsidies, this paper puts forward a new idea - establishing grain subsidies through assessing the value of the natural resources in Brain production. The assessment of the natural resources in Brain production provides rationale and reference standard for the policy of Brain subsidies, which will promote the sustainable use of natural resources accordingly. This paper concludes：（1） it is necessary for the grain subsidies to assess the full value of natural resources, including economic value, ecological value and social value：（2） the government should give farmers direct subsidies or environment subsidies according to the economic and ecological value of natural resources in grain production, （3） the social value of natural resources can be realized by establishing the country social security system, taking the social value as the criterion for the payment for part of farmers＇ insurance.

关键词： Grain production Natural resources: Value Grain subsidies

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Protein Content and Amino Acid Composition in Grains of Wheat-Related Species

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Agricultural Sciences in China 2008年第3期7卷 272-279页

作者： JIANG Xiao-ling TIAN Ji-chun hao Zhi zhang wei-dong State Key Laboratory of Crop Biology/Group of Quality Wheat Breeding Shandong Agricultural University Tai＇an 271018 P.R. China

The protein content and amino acid composition for 17 wheat-related species （WRS） and three common wheats （control） were determined and analyzed, and the essential amino acids （EAAs） in WRS were evaluated according to FAO/WHO amino acid recommendations. The results showed that the mean protein content for WRS was 16.67%, which was 23.21% higher than that for the control. The mean contents （g 100 g^-1 protein） of most amino acids for WRS were lysine 2.74%, threonine 2.83%, phenylalanine 4.17%, isoleucine 3.42%, valine 3.90%, histidine 2.81%, glutamic acid 29.96%, proline 9.12%, glycine 3.59%, alanine 3.37%, and cysteine 1.57%, which were higher than those for the control. The contents of the other 6 amino acids for WRS were lower than those for the control. The materials （Triticum monococcum L., Triticum carthlicum Nevski, and Triticum turgidum L.） contained relatively high concentration of the most deficient EAAs （lysine, threonine, and methionine）. Comparing with FAO/WHO amino acid recommendations, the amino acid scores （AAS） of lysine （49.8%）, threonine （70.7%）, and sulfur-containing amino acids （74.8%） were the lowest, which were considered as the main limiting amino acids in WRS. It was observed that the materials with Triticum urartu Turn. （AA） and Aegilops speltoides Tausch. （SS） genomes had relatively high contents of protein and EAA. The contents of protein （16.91%）, phenylalanine （4.78%）, isoleucine （3.53%）, leucine （6.16%）, and valine （4.09%） for the diploid materials were higher than those for the other materials. These results will provide some information for selecting parents in breeding about nutrient quality and utilization of fine gene in wheat.

关键词： wheat-related species protein content amino acid composition amino acid score

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A scheduling method based on a hybrid genetic particle swarm algorithm for multifunction phased array radar

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Frontiers of Information Technology & Electronic Engineering 2017年第11期18卷 1806-1816页

作者： hao-wei zhang Jun-wei XIE Wen-long LU Chuan SHENG Bin-feng ZONG Air and Missile Defense College Air Force Engineering University Xi'an 710051 China Troop 94225 Rizhao 276000 China Troop 94710 Wuxi 214000 China

A hybrid optimization approach combining a particle swarm algorithm, a genetic algorithm, and a heuristic interleaving algorithm is proposed for scheduling tasks in the multifunction phased array radar. By optimizing parameters using chaos theory, designing the dynamic inertia weight for the particle swarm algorithm as well as introducing crossover operation and mutation operation of the genetic algorithm, both the efficiency and exploration ability of the hybrid algorithm are improved. Under the frame of the intelligence algorithm, the heuristic interleaving scheduling algorithm is presented to further use the time resource of the task waiting duration. A large-scale simulation demonstrates that the proposed algorithm is more robust and efficient than existing algorithms.

关键词： Phased array radar Scheduling Particle swarm algorithm Genetic algorithm Pulse interleave

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Acute respiratory distress syndrome following multiple wasp stings treated with extracorporeal membrane oxygenation:A case report

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World Journal of Clinical Cases 2022年第30期10卷 11122-11127页

作者： Zheng-Yin Cai Bao-Ping Xu wei-hao zhang Huai-Wen Peng Qing Xu Huai-Bin Yu Quan-Gen Chu Shu-Sheng Zhou Department of Critical Care Medicine Traditional Chinese Hospital of Lu'an Affiliated to Anhui University of Traditional Chinese MedicineLu'an 237000Anhui ProvinceChina Department of Chinese Medicine Anhui University of Traditional Chinese MedicineHefei 230031Anhui ProvinceChina Department of Intensive Care Unit The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

BACKGROUND It is necessary for clinicians to be aware of a rare but possible acute respiratory distress syndrome(ARDS)complication caused by multiple wasp *** ARDS has a high mortality rate but no specific pharmacotherapies have been identified to *** case study presents the first case of severe ARDS caused by multiple wasp stings,treated successfully with extracorporeal membrane oxygenation(ECMO).It also emphasizes the effectiveness of early ECMO treatment for severe ARDS with persistent *** SUMMARY A 24-year-old woman was admitted to the emergency department after being stung by more than 10 wasps within a 30-min period,with clinical symptoms of multiple rashes,dizziness,chest tightness,nausea,and *** the 2nd day of admission,the patient developed progressive *** patient was diagnosed with ARDS based on clinical manifestations and lung computed tomography(CT)*** of the progressive dyspnea,the intensive care unit physician performed endotracheal intubation and continued to provide ventilator support,but the patient’s respiratory distress worsened,as indicated by the ratio of arterial partial pressure of oxygen to fraction of inspired ***-venous ECMO was initiated for 6 *** day 7 of admission,ECMO was *** the 11th day of admission,CT scan of the lungs revealed significant reduction of ground-glass opacities and *** about 2 wk,the patient recovered completely from ARDS and was discharged to *** the 2-mo follow-up,the patient was in good health with no recurrence of dyspnea nor chest *** ARDS complication caused by multiple wasp stings may be fatal when mechanical ventilation becomes dangerous due to persistent hypoxemia and despite optimization of ARDS *** propose that the early implementation of ECMO is a relatively effective treatment,although the evidence is relatively limited.

关键词： Wasp Bites and stings Respiratory distress syndrome Persistent hypoxemia Extracorporeal membrane oxygenation Case report

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MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang wei Ming Longfu Chen Tianliang Song Moxi Yele hao zhang Long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng Wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

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