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Effects of two silicone resin coatings on performance of FeSiAl magnetic powder cores

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Journal of Iron and Steel Research International 2024年第5期31卷 1279-1288页

作者： jia-qi liu Zheng-qu Zhu Pu Wang Yi-fan Li Jing Pang jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao266232ShandongChina

Two silicon resins with excellent thermal stability,JH1123 and JH7102,are used as the insulated agents and binders for the gas-atomized FeSiAl powder,and corresponding magnetic powder cores(MPCs)are *** insulation capability and application prospects of the two silicon resins are evaluated by comparing the magnetic properties of the coated powder and *** scanning electron microscopy,energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy results show that uniform insulation layers are both formed on the powder ***1123 has stronger binding ability,and the JH1123-coated powder exhibits severe agglomeration,with d50(average particle size)approximately twice that of the JH7102-coated *** as-prepared MPCs exhibit outstanding soft magnetic ***,the permeability of FeSiAl@JH1123 is up to 74.0,which is 35.5%higher than that of FeSiAl@JH7102 because JH1123 can further improve the density of the *** for FeSiAl@JH7102,it has better direct current bias and lower core loss of 716.9 mW cm^(−3) at 20 mT and 1000 kHz due to its lower coercivity and greater anti-magnetic saturation ability.A comprehensive comparison shows that FeSiAl@JH1123 is suitable for medium and high frequency applications,while FeSiAl@JH7102 is more suitable for high frequency *** indicates that the use of JH1123 and JH7102 silicon resins for binding and insulated coating not only simplifies the preparation process of MPCs,but also enables the controlled production of MPCs for different applications.

关键词： FeSiAl Insulated coating Magnetic powder core Permeability Core loss

Experimental and numerical investigations of the collapse of a laser-induced cavitation bubble near a solid wall

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Journal of Hydrodynamics 2022年第2期34卷 189-199页

作者： jia-yun Zhang Yu-xin Du jia-qi liu Yu-rong Sun Zhi-feng Yao qiang Zhong College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Water Supply Network System Safety and Energy Saving Engineering Technology China Agricultural UniversityBeijing100083China

With the collapse of cavitation bubbles near the wall,micro-jets and shock waves will be formed,to generate a high-pressure load and to cause the cavitation damage on the surface of the hydraulic *** to the rapid development of the cavitation bubble collapse process(in the time scale of hundred nanoseconds),the time resolution of the conventional high-speed cameras should reach more than one million frames per second,which will limit the spatial resolution,and obscure the details of the cavitation bubble shape near the cavitation bubble collapse *** this paper,with the help of the laser cavitation bubble photogrammetry system with nanosecond-micron space-time resolution,the experiment is carried out for the cavitation bubble collapse morphology evolution near the *** morphological characteristics of the cavitation bubble collapse at specific times are *** the help of the OpenFOAM code,the collapse process of the cavitation bubble near the solid wall is *** is shown that the cavitation bubble near the wall collapses in an axial symmetric heart shape and the micro-jet directed to the wall will pull the cavitation bubble towards the *** counter-jet generated in the rebound stage will drive the cavitation bubble to move away from the *** numerical simulation of the cavitation bubble shape in the collapse period is well consistent with the experimental results,but the ability to capture the shock wavefront needs to be *** the conditions studied in this paper,the cavitation bubble collapse micro-jet velocity can reach up to a hundred meters per second both in the experiment and the numerical simulation.

关键词： Near wall cavitation collapse micro-jet shock wave

Simulation and experiment investigations on fabrication of Fe-based amorphous powders by a novel atomization process equipped with assisted gas nozzles

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Journal of Iron and Steel Research International 2023年第6期30卷 1142-1155页

作者： jia-qi liu Yan-nan Dong Pu Wang Huan Zhao Jing Pang Xiao-yu Li jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao 266232ShandongChina

Based on computational fluid dynamics method,the effect of atomization gas pressure on the atomization efficiency of Laval nozzle was studied,and then a discrete phase model was established and combined with industrial trials to study the effect of a new type of assisted gas nozzles(AGNs)on powder size distribution and amorphous powder *** results show that increasing the atomization pressure can effectively improve the gas velocity for the Laval nozzle;however,it will decrease the aspiration pressure,and the optimal atomization pressure is 2.0 *** with this,after the application of AGNs with the inlet velocity of 200 m s^(-1),assisted gas jet can increase the velocity of overall droplets in the break-up and solidification area by 40 m s^(-1) and the maximum cooling rate is increased from 1.9×10^(4) to 2.3×10^(4) K s^(-1).The predicted particle behavior is demonstrated by the industrial trails,that is,after the application of AGNs,the median diameter of powders d50 is decreased from 28.42 to 25.56 lm,the sphericity is increased from 0.874 to 0.927,the fraction of amorphous powders is increased from 90.4% to 99.4%,and only the coercivity is increased slightly due to the accumulation of internal *** is illustrated that the AGNs can improve the yield of fine amorphous powders,which is beneficial to providing high-performance raw powders for additive manufacturing technology.

关键词： Computational fluid dynamics Atomization Assisted gas nozzle Discrete phase model Amorphous powder

Stent fracture after transjugular intrahepatic portosystemic shunt placement using the bare metal stent/stent-graft combination technique

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World Journal of Gastrointestinal Surgery 2023年第10期15卷 2133-2141页

作者： qi-jia liu Xiao-Feng Cao Yun Pei Xuan Li Guo-Xiang Dong Chang-Ming Wang Department of Interventional Radiology and Vascular Surgery Peking University Third HospitalBeijing 100191China Department of Interventional Therapy Yangquan First People’s HospitalYangquan 045000Shanxi ProvinceChina

BACKGROUND A transjugular intrahepatic portosystemic shunt(TIPS)is widely placed to treat portal *** the Viatorr®stent(*** and Associates,Flagstaff,AZ,United States)is not available in all hospitals in China,the bare metal stent(BMS)/stent-graft combination technique is still popular for TIPS *** fracture is a complication after TIPS placement using this technique,with limited available literature focusing on *** To assess the incidence of stent fracture after TIPS placement using the BMS/stent-graft combination technique and to identify the risk factors for stent *** proposed technique modifications to improve the clinical results of TIPS placement with the BMS/stent-graft combination *** We retrospectively analyzed the computed tomography(CT)data of all patients with portal hypertension who underwent the TIPS procedure between June 2011 and December 2021 in a single *** implanted with the BMS/stent graft and had follow-up imaging data available were *** identified patients with stent fracture and analyzed their *** logistic regression was applied to identify the potential predictors of stent *** Of the 68 included patients,stent fracture occurred in seven(10.3%)*** on CT images,the stent fractures were categorized into three *** study consisted of four(57.1%)type I fractures,one(14.3%)type II fracture,one(14.3%)type IIIa fracture,and one(14.3%)type IIIb *** adjusting for covariates,multivariable logistic regression revealed that the risk factors for stent fracture were the implantation of a greater number of stents[adjusted odds ratio(aOR)=22.2,95%confidence interval(CI):1.2-415.4,P=0.038]and a larger proximal sagittal stent bending angle(aOR=1.1,95%CI:1.0-1.3,P=0.020).CONCLUSION Stent fracture occurred in approximately 10%of patients with portal hypertension who underwent TIPS with the BMS/stent-graft combination tec

关键词： Portal hypertension Transjugular intrahepatic portosystemic shunt Stent fracture Bare metal stent/stent-graft combination Risk factor Fracture types

Genome and population evolution and environmental adaptation of Glyptosternon maculatum on the qinghai-Tibet Plateau

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Zoological Research 2021年第4期42卷 502-513页

作者： Shi-Jun Xiao Zen-Bo Mou Rui-Bin Yang Ding-Ding Fan jia-qi liu Yu Zou Shi-Lin Zhu Ming Zou Chao-Wei Zhou Hai-Ping liu Institute of Fisheries Science Tibet Academy of Agricultural and Animal Husbandry SciencesLhasaTibet 810000China Department of Computer Science Wuhan University of TechnologyWuhanHubei 430070China College of Fisheries Huazhong Agricultural UniversityWuhanHubei 430070China Key Laboratory of Freshwater Fish Reproduction and Development(Ministry of Education) College of FisheriesSouthwest UniversityChongqing 402400China College of Plant Protection Jilin Agriculture UniversityChangchunJilin 130118China jiaxing Key Laboratory for New Germplasm Breeding of Economic Mycology JiaxingZhejiang 314000China

Persistent uplift means the qinghai-Tibet Plateau(QTP)is an ideal natural laboratory to investigate genome evolution and adaptation within highland ***,how paleogeographic and paleoclimatic events influence the genome and population of endemic fish species remains *** maculatum is an ancient endemic fish found on the QTP and the only critically endangered species in the Sisoridae ***,we found that major transposons in the *** genome showed episodic bursts,consistent with contemporaneous geological and climatic events during the QTP ***,histone genes showed significant expansion in the *** genome,which may be mediated by long interspersed nuclear elements(LINE)repetitive element *** analysis showed that ancestral *** populations experienced two significant depressions 2.6 million years ago(Mya)and 10000 years ago,exhibiting excellent synchronization with Quaternary glaciation and the Younger Dryas,***,we propose that paleogeography and paleoclimate were dominating driving forces for population dynamics in endemic fish on the *** movements and temperature fluctuation likely destroyed the habitat and disrupted the drainage connectivity among *** factors may have caused severe bottlenecks and limited migration among ancestral *** populations,resulting in the low genetic diversity and endangered status of the species today.

关键词： qinghai-Tibet Plateau(QTP) Glyptosternon maculatum Genome evolution Population High-altitude adaptation

维普期刊数据库

Research progress of stem cells on glaucomatous optic nerve injury

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International Journal of Ophthalmology(English edition) 2016年第8期9卷 1226-1229页

作者： Ya-Sha Zhou jian Xu Jun Peng Ping Li Xiao-Juan Wen Yue liu Ke-Zhu Chen jia-qi liu Ying Wang qing-Hua Peng Ophthalmology of Integration of Traditional Chinese Medicine Hunan University of Traditional Chinese Medicine Department of Ophthalmology the No.1 People's Hospital of Ningbo Hunan University of Traditional Chinese Medicine Department of Ophthalmology the First Affiliated Hospital of Hunan University of Traditional Chinese Medicine

Glaucoma, the second leading cause of blindness, is an irreversible optic neuropathy. The mechanism of optic nerve injury caused by glaucoma is undefined at present. There is no effective treatment method for the injury. Stem cells have the capacity of self-renewal and differentiation. These two features have made them become the research focus on improving the injury at present. This paper reviews the application progress on different types of stem cells therapy for optic nerve injury caused by glaucoma.

关键词： stem cells glaucoma optic nerve injury research progress

Economic effect of China's carbon neutrality target under shared socioeconomic pathways

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Science China Earth Sciences 2025年第1期68卷 142-157页

作者： Zemiao liu Xianjin HUANG Xinxian qi School of Geography and Ocean Science Nanjing University Key Laboratory of Carbon Neutrality and Territory Optimization Ministry of Natural Resources Frontiers Science Center for Critical Earth Material Cycling Nanjing University

Economic feasibility is crucial for achieving the carbon neutrality target. However, current integrated assessments often underestimate the economic impacts of mitigation policies due to the lack of consideration of their economic benefits. This study integrates a warming-labour productivity model with a typical integrated assessment model using shared socioeconomic pathways. It simulates China's economic development and carbon emission levels under both baseline and carbon-neutral policy scenarios, evaluating the economic costs and benefits of emission reduction policies aimed at achieving carbon neutrality. These findings reveal the following:(1) The economic costs of emission reduction policies are projected to peak between 2050 and 2060, ranging from 0.41% to 9.37% of total GDP in the baseline scenario, primarily due to increased energy prices and R&D investments. These costs are expected to decline rapidly after 2070.(2) China's carbon-neutral policies will mitigate global warming, with the economic benefits of mitigation projected to reach 5.65% to 17.24% of China's total GDP by 2100.(3) Lowcarbon scenarios SSP1 and SSP4 could significantly reduce initial economic costs and advance the onset of net economic gains to 2060. This integrated assessment confirms that China's carbon neutrality target offers substantial net economic benefits in the long term. To minimize initial economic costs, efforts should focus on enhancing consumption-side transitions, upgrading lowcarbon technologies, and adopting new energy sources.

关键词： Climate change China Carbon neutrality Economic effects Policy

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Exponential decay law of acoustic emission and microseismic activities caused by disturbances associated with multilevel loading and mining blast

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Transactions of Nonferrous Metals Society of China 2021年第11期31卷 3549-3563页

作者： Shi-da XU Tian-xiao CHEN jia-qi liu Chen-rui ZHANG Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China

To investigate decay law of acoustic emission and microseismic activities caused by disturbances associated with multilevel loading and mining blast,a new exponential decay(ED)law was *** results show that the micro-fracture activity decay law after multistage stress loading and blasting disturbance conforms to the ED model,in which the sum of A and n represents the number of initial micro-fracture events,and n represents the level of background micro-fracture *** ED model can describe the number of initial micro-fracture events with a deviation less than 10%.The ED model outperforms the traditional aftershock models in describing the micro-fracture event decay law in the three cases *** ED model can provide a reference for selecting the blasting interval in mines,which is of great significance to maintain the stability of the surrounding rock and ensure safe production in metal mines.

关键词： exponential decay law blast disturbance acoustic emission microseismic activities metal mine

维普期刊数据库

Accuracy of multi-echo Dixon sequence in quantification of hepatic steatosis in Chinese children and adolescents

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World Journal of Gastroenterology 2019年第12期25卷 1513-1523页

作者： Yu-Zhen Zhao Yun-Gen Gan jian-Li Zhou jia-qi liu Wei-Guo Cao Shu-Mei Cheng Da-Ming Bai Meng-Zhu Wang Fang-qin Gao Shao-Ming Zhou Department of Gastroenterology Shenzhen Children's Hospital Department of Radiology Shenzhen Children's Hospital Department of Physical Examination Futian District Maternity and Child Healthcare Hospital Department of MR Scientific Marketing Siemens Healthineers Department of MR Clinical Marketing Siemens Healthineers

BACKGROUND Nonalcoholic fatty liver disease(NAFLD) is currently the outstanding cause of chronic liver disease in children and adolescents, especially in overweight and obese groups. Liver biopsy is the reference standard to diagnose NAFLD but invasive, thus it is not the best choice in clinical diagnosis and *** resonance(MR) is widely used in clinical trials to noninvasively quantify liver fat content in adults and children in foreign countries. While currently, it is rarely used in Chinese children and adolescents. We postulated that quantifying hepatic steatosis by MR could be extended to children and adolescents in *** To investigate the accuracy of MR imaging(MRI) in quantifying liver fat with MR spectroscopy(MRS) as a reference. A secondary goal was to assess the prevalence of NAFLD in overweight and obese Chinese children and *** were 86 children and adolescents enrolled in this study, including 65 overweight and obese children and 21 healthy children. The participants underwent MRI and MRS. MRI and MRS were performed using multi-echo Dixon and HISTO sequences, respectively, to calculate hepatic proton density fat fraction(PDFF). Hepatic steatosis was diagnosed using MRS-PDFF > 5% as the threshold. Spearman's analysis was used to evaluate the correlation between MRI and MRS. The agreement between these two methods was assessed by BlandAltman *** The MRI-PDFF in the MRS region of interest and the entire liver was 9.9% ±10.3% with a range of 0.3%-39.9%, and 10.6% ± 9.4% with a range of 1.9%-38.9%,respectively. The MRS-PDFF was 9.1% ± 10.0%, with a range of 0.5%-37.8%. The incidence of hepatic steatosis detected by MRS-PDFF was 46.5%(40/86) of all participants, all of whom belonged to the overweight and obese ***'s analysis indicated an excellent correlation between multi-echo Dixon and MRS(r > 0.9, P < 0.01). Bland-Altman analysis also demonstrated a good agreement between these two ***

关键词： Nonalcoholic fatty liver disease Magnetic resonance imaging Magnetic resonance spectroscopy Children and adolescents Hepatic steatosis