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Analysis of diffusion behavior of harmful emissions from trackless rubber-wheel diesel vehicles in underground coal mines

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International Journal of Mining Science and Technology 2022年第6期32卷 1285-1299页

作者： yun Hua Wen nie Qiang Liu Xiaofei Liu Chengyi Liu Weiwei Zhou Fengning Yu College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

To define the diffusion behavior of harmful exhaust substances from diesel vehicles and support safety risk assessments of underground coal mines,we performed a multi-species coupling calculation of the emission and diffusion of harmful substances from a trackless rubber-wheel diesel vehicle.A computational fluid dynamics(CFD)model of the diffusion of harmful emissions was hence established and *** the perspective of risk analysis,the diffusion behavior and distribution of hazardous substances emitted by the diesel vehicle were studied under 4 different conditions;moreover,we identified areas characterized by hazardous levels of *** the vehicle idled upwind in the roadway,high-risk areas formed behind and to the right of the vehicle:particularly high concentrations of pollutants were measured near the rear floor of the vehicle and within 5 m behind the *** the vehicle idled downwind,high-risk areas formed in front of it:particularly high concentrations of pollutants were measured near the floor and within 5 m from the front of the *** the above cases,the driver would not breathe highly polluted air and would be relatively *** the vehicle idled into the chamber,however,high-risk areas formed on both sides of the vehicle and near the upper *** entry of the vehicle caused a greater increase in the concentration of pollutants in the chamber and in the driver’s breathing zone compared with reverse entry.

关键词： Diesel vehicle Harmful emissions Diffusion behavior CFD model Underground coal mine

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Preparing High Silicon Steel by Sintering Fe-6.5%Si Powder Compacts in Static Magnetic Field

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Journal of Iron and Steel Research International 2012年第S1期19卷 455-458页

作者： TANG nie-wei zhong yun-bo SUN Zong-qian ZHENG Tian-xiang Shanghai Key Laboratory of Modern Metallurgy & Material Processing Shanghai University

In this research,sintering Fe-6.5wt%Si Compact specimen in static magnetic field is proposed for preparing high silicon *** is found that the densifications of the compacts are affected remarkably by superimposing magnetic *** density of the compacts can be increased when the MFD is higher than 0.2 *** highest relative density of the samples is 97.2%.The magnetic property of silicon steel could be improved when superimpose static magnetic field in sintering process,the permeability of the compact are two times of that without magnetic field,and the magnetic property parallel to the direction of the magnetic field was evidently higher than that in perpendicular direction.

关键词： 6.5wt%Si high silicon steel static magnetic field sintering orientation magnetic property

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Individual Identification of Electronic Equipment Based on Electromagnetic Fingerprint Characteristics

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China Communications 2021年第1期18卷 169-180页

作者： Han Xu Hongxin Zhang Jun Xu Guangyuan Wang yun nie Hua Zhang School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Aerospace Vehicle Design Department Beijing ChinaBeijing 100876China

With the rapid development of communication and computer,the individual identification technology of communication equipment has been brought to many application *** identification of the same type of electronic equipment is of considerable significance,whether it is the identification of friend or foe in military applications,identity determination,radio spectrum management in civil applications,equipment fault diagnosis,and so *** of the limited-expression ability of the traditional electromagnetic signal representation methods in the face of complex signals,a new method of individual identification of the same equipment of communication equipment based on deep learning is *** contents of this paper include the following aspects:(1)Considering the shortcomings of deep learning in processing small sample data,this paper provides a universal and robust feature template for signal *** paper constructs a relatively complete signal template library from multiple perspectives,such as time domain and transform domain features,combined with high-order statistical *** on the inspiration of the image texture feature,characteristics of amplitude histogram of signal and the signal amplitude co-occurrence matrix(SACM)are proposed in this *** signal features can be used as a signal fingerprint template for individual identification.(2)Considering the limitation of the recognition rate of a single classifier,using the integrated classifier has achieved better generalization *** final average accuracy of 5 NRF24LE1 modules is up to 98%and solved the problem of individual identification of the same equipment of communication equipment under the condition of the small sample,low signal-to-noise ratio.

关键词： signal fingerprints histogram-based signal feature starting point detection signal level cooccurrence matrix ensemble Learningn

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SiO_(2)改性Ce-V-W/Ti催化剂载体的抗碱(土)金属中毒性能

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化工进展 2025年第1期44卷 266-276页

作者：庄柯陈宏许芸仲兆平周峻伍周凯董月红国家能源集团科学技术研究院有限公司低碳智能燃煤发电与超净排放全国重点实验室江苏南京210023 东南大学能源与环境学院能源热转换及其过程测控教育部重点实验室江苏南京211189

为了提升Ce-V-W/Ti催化剂耐碱(土)金属中毒性能,本文使用溶胶-凝胶法制备了TiO_(2)载体并进行了SiO_(2)掺杂改性,通过浸渍法制备了Ce-V-W/Ti-Si催化剂。采用浸渍法模拟了CaCO_(3)、K_(2)O等碱物种中毒,探究了SiO_(2)改性载体对催化剂的... 详细信息

为了提升Ce-V-W/Ti催化剂耐碱(土)金属中毒性能,本文使用溶胶-凝胶法制备了TiO_(2)载体并进行了SiO_(2)掺杂改性,通过浸渍法制备了Ce-V-W/Ti-Si催化剂。采用浸渍法模拟了CaCO_(3)、K_(2)O等碱物种中毒,探究了SiO_(2)改性载体对催化剂的脱硝活性和抵御碱(土)金属中毒性能的影响,并使用X射线光电子能谱、N_(2)吸附-脱附、H2-程序升温还原、NH_(3)-程序升温脱附等表征手段对催化剂进行了表征分析。实验结果表明,对Ce-V-W/Ti催化剂载体进行SiO_(2)改性会降低其中低温段的脱硝活性,但能明显提升催化剂对碱物种的耐受性,总体上,Ce1V1W7/Ti-Si4对碱物种的耐受性最好,各类碱物种对其脱硝活性的毒害程度为K_(2)O>Na_(2)O>CaCO_(3)>CaO>CaSO_(4)。表征结果显示,SiO_(2)改性削弱了催化剂表面Ce氧化物活性,但显著增加了催化剂的比表面积和酸性位点数量,并在催化剂碱中毒时保护了活性金属氧化物的还原性。

关键词：选择催化还原催化剂载体活性 SiO_(2)改性碱中毒

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冬季横断山区一次低空风切变诊断及模拟

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应用气象学报 2025年第1期36卷 77-89页

作者：任菊章杨雪陶云付志嘉陈艳钟亚含王曼金燕云南省气象科学研究所昆明650034 云南机场集团有限责任公司沧源佤山机场临沧677400 大理国家气候观象台大理671003 云南省气候中心昆明650034

沧源佤山机场位于横断山区得龙山,冬季飞机在起飞着陆过程中易遭遇低空风切变,造成复飞。应用机场气象站资料、自动气象站和风廓线雷达加密观测资料等,诊断分析了2021年12月29日沧源佤山机场区域出现的一次低空风切变复飞事件。结果表明... 详细信息

沧源佤山机场位于横断山区得龙山,冬季飞机在起飞着陆过程中易遭遇低空风切变,造成复飞。应用机场气象站资料、自动气象站和风廓线雷达加密观测资料等,诊断分析了2021年12月29日沧源佤山机场区域出现的一次低空风切变复飞事件。结果表明:冬季一般天气条件下,横断山区盛行偏西南气流,沧源佤山机场东侧坝区存在小尺度局地山谷风环流。午后盛行风加强,机场地面转为一致的西南风,风速增加并超过5.0 m·s^(-1)后,机场东侧坝区谷风风速增加,并伴有垂直上升运动。随着太阳辐射减弱,盛行风开始减弱,东侧坝区内转为山风环流。数值模拟结果也显示:午后盛行偏西南风增强,促使机场地面风速和影响东侧坝区的下坡气流加速,与谷风在机场东侧坝区辐合,产生上升气流,上下层动量交换加强,边界层垂直不稳定加强,产生低空风切变,造成复飞。因此,边界层盛行风与局地谷风环流间的相互作用是造成2021年12月29日佤山机场东侧坝区出现瞬时低空风切变的主要原因。

关键词：低空风切变过山气流山谷风环流数值模拟

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Left-definite boundary conditions of Sturm-Liouville problems when the interval shrinks to a point

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 29-37页

作者： GAO yun-lan WANG zhong WU Hong-you Department of Mathematics Inner Mongolia University of Technology Huhhot 010051 China Department of Mathematics ZhaoQing University Zhaoqing 526061 China Department of Mathematics Northern Illinois University DeKalb IL60115 USA

On the condition that the interval of the problem shrinks to a point, we investigated the separated boundary conditions Sα,β of left-definite Sturm-Liouville problem, and answered the following question： Is there a co ∈ J such that Sα,β is always left-definite or semi-left-definite for the Sturm-Liouville equation for each c ∈ （a, co）？

关键词： Left-definite Sturm-Liouville problem semi-left-definite Sturm-Liouville problem separatedboundary condition.

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Enantioselective Degradation of Rac-Metolachlor and S-Metolachlor in Soil

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Pedosphere 2006年第4期16卷 489-494页

作者： MA yun LIU Wei-Ping WEN Yue-zhong Institute of Environmental Science Zhejiang University P. O. Box 31 74 Hangzhou 310029 （China） Researeh Center of Green Chirality College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310015 （China）

Separation of chiral enantiomers and the dissipation of rac-metolachlor and S-metolachlor in soil were evaluated using achiral high-performance liquid chromatography (HPLC) and chiral gas chromatography (GC) methods. Under the experimental conditions the possible metabolite was considered to be N-(2-ethyl-6-methyl-phenyl)-2-hydroxy-acetamide. Because of the presence of two chiral elements (asymmetrically substituted carbon and chiral axis), the baseline separation of metolachlor enantiomers was not achieved. S-metolachlor degraded faster in soil than rac-metolachlor. After a 42-day incubation, 73.4% of rac-metolachlor and 90.0% of S-metolachlor were degraded. However, due to the absence of biological processes the degradation process in sterilized soil showed no enantioselectivity. The results indicated that enantioselective degradations could greatly affect the environmental fate of metolachlor and should be considered when the environmental behavior of these compounds was assessed.

关键词： chiral separation degradation rac-metolachlor S-metolachlor soil

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The Chen-Ruan Cohomology of Almost Contact Orbifolds

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Acta Mathematica Sinica,English Series 2010年第1期26卷 77-88页

作者： Fan DING yun Feng JIANG Jian zhong PAN School of Mathematics Peking University Beijing 100871 P. R. China Department of Mathematics University of Utah 155S 1400E JWB233 Salt Lake City UT 84112 USA Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

Comparing to the Ch-~Ruan cohomology theory for the almost complex orbifolds, we study the orbifold cohomology theory for almost contact orbifolds. We define the Chen-Ruan cohomology group of any almost contact orbifold. Using the methods for almost complex orbifolds, we define the obstruction bundle for any 3-multisector of the almost contact orbifolds and the Chen^Ruan cup product for the Che-Ruan cohomology. We also prove that under this cup product the direct sum of all dimensional orbifold cohomology groups constitutes a cohomological ring. Finally we calculate two examples.

关键词： almost contact orbifolds Chen Ruan cohomology twisted sectors almost complex orbifold

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Platelet activation relieves liver portal hypertension via the lymphatic system though the classical vascular endothelial growth factor receptor 3 signaling pathway

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World Journal of Gastroenterology 2025年第10期31卷 86-102页

作者： Min Chen Jin-Bo Zhao Guang-Bo Wu Zheng-Hao Wu Gu-Qing Luo Zhi-Feng Zhao Chi-Hao Zhang Jia-yun Lin Hong-Jie Li Xiao-Liang Qi Hai-zhong Huo Abudukadier Tuersun Qiang Fan Lei Zheng Meng Luo Department of General Surgery Ninth People’s Hospital Affiliated to Shanghai Jiao Tong UniversitySchool of MedicineShanghai Jiao Tong UniversityShanghai 200011China Department of Urology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Xijing Hospital of Digestive Diseases Air Force Military Medical UniversityXi’an 710032Shaanxi ProvinceChina

BACKGROUND Liver cirrhosis and portal hypertension(PHT)can lead to lymphatic abnormalities and coagulation *** lymphangiogenesis may relieve liver cirrhosis and PHT,the present study investigated the gene expression alterations in the lymphatic system and the effectiveness of platelet-mediated lymphangiogenesis in improving liver cirrhosis and *** To investigate the role of lymphangiogenesis in preclinical PHT *** Immunohistochemistry and transcriptome sequencing of bile duct ligation(BDL)and control lymphatic samples were conducted to reveal the indicated signaling *** enrichment analyses were performed on the differentially expressed genes and hub *** infection of vascular endothelial growth factor C(VEGF-C),plateletrich plasma(PRP),and VEGF3 receptor(VEGFR)inhibitor MAZ-51 was used as an intervention for the lymphatic system in PHT ***,hemodynamic tests and western blot analyses were performed to demonstrate the effects of lymphatic intervention in PHT *** Lymphangiogenesis was increased in the BDL rat *** sequencing analysis of the extrahepatic lymphatic system revealed its close association with platelet adherence,aggregation,and *** role of PHT in the rat model was investigated by activating(PRP)and inhibiting(MAZ-51)the lymphatic *** promoted lymphangiogenesis,which increased lymphatic drainage,alleviated portal pressure,reduced liver fibrosis,inhibited inflammation,inhibited angiogenesis,and suppressed mesenteric artery ***-51 reversed the above *** Via VEGF-C/VEGFR-3,platelets impede fibrosis,angiogenesis,and mesenteric artery remodeling,ultimately alleviating ***,platelet intervention is a therapeutic approach for cirrhosis and PHT.

关键词： Portal hypertension Cirrhosis Lymphangiogenesis Platelets Vascular endothelial growth factor C

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Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2004年第z1期14卷 140-143页

作者： GUO zhong-cheng ZHU Xiao-yun XU Rui-dong Center of Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating were studied. The results show that hardness of the pulse current electrodeposited composite coatings is higher than that of the direct current electrodeposited composite coatings while other parameters are the same. Otherwise, the deposited velocity is higher, and wear resistance and corrosion resistance of the pulse current electrodeposited composite coatings are also improved when the average current density is 10 A/dm2 , pulse frequency is 800 Hz and duty ratio is 1: 5. The hardness of the coating as-deposited is HV500 - 700, and it reaches HV1300 after heat treatment at 400 ℃ for 1 h.

关键词： RE-Ni-W-P-SiC composite coating pulse current electrodeposition properties

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