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一种统计RELAX方法的ISAR成像研究

西安电子科技大学学报 2010年第6期37卷 1065-1070,1124页

作者：张龙李亚超苏军海邢孟道西安电子科技大学雷达信号处理国家重点实验室陕西西安710071 西安工程大学电子与信息学院陕西西安710048

针对在传统超分辨ISAR成像中仅依靠能量判断距离单元中的散射点数目可能会引起虚假点或散射点漏检的问题,提出了一种统计RELAX超分辨ISAR成像方法,该方法充分将目标所处环境的背景噪声与杂波的统计信息用于散射点的提取中,按照期望的虚... 详细信息

针对在传统超分辨ISAR成像中仅依靠能量判断距离单元中的散射点数目可能会引起虚假点或散射点漏检的问题,提出了一种统计RELAX超分辨ISAR成像方法,该方法充分将目标所处环境的背景噪声与杂波的统计信息用于散射点的提取中,按照期望的虚警率设置检测门限,对所有的距离单元的回波信号进行高斯性检测,确定存在散射点的距离单元,最后利用统计RELAX超分辨技术进行散射点的提取并最终成像.实测数据的处理结果验证了该方法的虚假点远少于传统方法,并且可充分表现目标的几何细节特征.

关键词：高斯性检测逆合成孔径雷达成像统计RELAX 虚警概率

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岩石边坡基质-植被系统中氮磷钾损失模型

生态学杂志 2014年第11期33卷 3164-3168页

作者：邱利平李绍才孙海龙四川大学生命科学学院成都610064 川大学水利水电国家重点实验室成都610064

以岩石边坡基质-植被系统为研究对象,结合人工模拟降雨试验和养分损失模型,对基质径流养分损失量与降雨场次、降雨时间之间的关系进行了定量分析及预测。降雨试验中,N、P、K营养元素损失量与降雨场次呈负向关系,但随着降雨场次的增加,... 详细信息

以岩石边坡基质-植被系统为研究对象,结合人工模拟降雨试验和养分损失模型,对基质径流养分损失量与降雨场次、降雨时间之间的关系进行了定量分析及预测。降雨试验中,N、P、K营养元素损失量与降雨场次呈负向关系,但随着降雨场次的增加,损失量减少幅度变小;营养元素累积损失量随降雨时间呈幂函数增长;营养元素损失量在降雨场次和降雨时间变化上均表现出极显著差异(P=0.00)。养分损失模型能较准确地对径流养分损失量进行预测,确定系数均在0.86以上,实测结果与拟合预测结果接近,其相对误差<27%。其中,K在第一场降雨时,模型预测结果最好;N、P则在最后一场降雨时,预测效果最为显著。该模型的建立,可描述营养元素径流损失量随降雨时间的变化过程,从而为岩石边坡基质-植被系统制定合理的养分配比提供理论依据。

关键词：岩石边坡基质营养元素损失量模型

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剪切强化络合-超滤技术处理含锰废水

矿冶工程 2020年第1期40卷 92-95,100页

作者：钦梦园邱运仁中南大学化学化工学院

在络合-超滤过程中引入旋转盘强化过滤过程处理含锰废水,选择马来酸-丙烯酸共聚物(PMA)作为络合剂,主要探究了PMA和Mn(Ⅱ)形成络合物PMA-Mn的剪切稳定性。实验结果表明,pH=6、P/M(络合剂/金属离子质量浓度比)=12为PMA与Mn(Ⅱ)的最佳络... 详细信息

在络合-超滤过程中引入旋转盘强化过滤过程处理含锰废水,选择马来酸-丙烯酸共聚物(PMA)作为络合剂,主要探究了PMA和Mn(Ⅱ)形成络合物PMA-Mn的剪切稳定性。实验结果表明,pH=6、P/M(络合剂/金属离子质量浓度比)=12为PMA与Mn(Ⅱ)的最佳络合条件,此时Mn(Ⅱ)截留率高达99.1%;pH=4、5、6时,PMA-Mn络合物分别在800、1200、1400 r/min临界转速下发生解络,对应的临界剪切速率分别为5.32×10^4、1.10×10^5和1.47×10^5 s^-1;通过剪切诱导解络,可高效再生PMA。

关键词：马来酸-丙烯酸共聚物络合剂旋转盘络合-超滤剪切强化膜分离技术解络废水处理锰离子

Simultaneous Determination of Six Compounds in Rat Plasma by Ultra-Performance Liquid Chromatography with Tandem Mass Spectrometry: Application in the Pharmacokinetic Study of Qing Gan-Shu Yu-Fang

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World Journal of Traditional Chinese Medicine 2019年第4期5卷 250-259页

作者： Hai Jiang A-Jiao Houa Yan-Yan Zhang Wen-Jing Man Liu Yang Yong-Hai meng Xin-Yue Guo Song Wang Jia-Xu Zhang Bing-You Yang qiu-Hong Wang Kelvin Chan Hai-Xue Kuang College of Pharmacy Key Laboratory of Chinese Materia MedicaHeilongjiang University of Chinese MedicineMinistry of EducationHarbin College of Pharmacy Guangdong Pharmaceutical UniversityGuangzhouPR China Centre for Complementary Medicine Research The University of SydneySydneyNSW 2006Australia

A rapid and high selective ultra-performance liquid chromatography(UPLC)with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin,paeoniflorin,picroside I,picroside II,saikosaponin A,and saikosaponin D in rat plasma was developed and validated using butyl p-hydroxybenzoate as an internal ***-step direct protein precipitation with acetonitrile was used to extract the compounds from the rat plasma *** separation was achieved using an ACQUITY UPLC BEH C18 column(100 mm×2.1 mm,1.7μm)at a flow rate of 0.4 m L/min,using gradient mode containing 0.1%formic acid in water and acetonitrile were used as the Mobile phase A and *** ionization in negative ion mode and multiple reaction monitoring were used to identify and quantify active *** curves showed good linearity(R^2>0.9908)over a wide concentration range for all *** intra-and interday precision(relative standard deviation)ranged 2.4%–7.0%and 2.6%–8.0%,*** accuracy(relative error)was from-13.0%to 13.2%at all quality control *** recovery ranged from 81.1%to 92.5%.The validated method was successfully applied to pharmacokinetic study in rats after oral administration of Qing Gan-Shu *** results show that one can draw a conclusion that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo.

关键词： Pharmacokinetics traditional Chinese medicine prescriptions ultra-performance liquid chromatography with tandem mass spectrometry

Surface microtopography and micromechanics of various rank coals

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International Journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1351-1363页

作者： Xiang-hui Tian Da-zhao Song Xue-qiu He Hui-fang Liu Wei-xiang Wang Zhen-lei Li Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mine University of Science and Technology BeijingBeijing 100083China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China School of Civil Mining and Environmental EngineeringUniversity of WollongongWollongong NSW 2522Australia

For a long time,coalbed gas has brought about various problems to the safety of coal mine *** addition,the mining of gas and coalbed methane(CBM)has attracted much *** occurrence and migration of CBM are believed to be closely related to the micro-surface properties of *** further explore the characteristics of CBM occurrence and migration,in this study,the micro-surface topography,adhesion,and elastic modulus of five metamorphic coals were measured by atomic force microscopy(AFM).The results show that the microtopography of coal fluctuates around 40 nm,reaching a maximum of 66.5 nm and the roughness of the surface decreases with the increase of *** elastic modulus of coal micro-surface varies from 95.40 to 9626.41 MPa,while the adhesion varies from 15.08 to 436.22 nN,and they both exhibit a trend of"M"shape with the increase of ***,a high correlation exists between adhesion and microtopography *** most cases,the adhesion is larger in the concavity area and smaller in the convexity *** research results may provide a new method for revealing the occurrence and migration of CBM and ensure efficient and safe CBM exploitation.

关键词： coal atomic force microscopy microtopography adhesion elastic modulus

Relationship between syndrome elements and anterior communicating artery opening in patients with smptomatic severe carotid artery stenosis/occlusion

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Digital Chinese Medicine 2021年第1期4卷 64-70页

作者： ZHEN Fei meng Fanxing DOU Jinjuan Louis Lei Jin qiu Jiwen Neurology ward 5 Dongzhimen Hospital of Beijing University of Chinese MedicineBeijing 101100China Neurology ward 1 Dongfang Hospital of Beijing University of Chinese MedicineBeijing 100078China International Institute of Systems Medicine Inc.Milwaukee 53222USA School of Acupuncture-Moxibution and Tuina Tianjin University of Traditional Chinese MedicineTianjin 301617China

Objective To study the relationship between syndrome elements and anterior communicating artery(ACoA)opening in patients with symptomatic severe carotid artery stenosis/*** Thirty-six patients with symptomatic severe carotid stenosis/occlusion were collected,including 26 patients with cerebral infarction and 10 patients with transient ischemic attack(TIA).Syndrome elements at five time points were *** tomography angiography(CTA)combined with magenic resonance angiograp(MRA)was used to evaluate the primary collateral circulation,and the prognosis and syndrome elements were statistically analyzed according to whether the ACoA was open or *** The ACoA was open more in the primary collateral circulation among patients with symptomatic severe carotid stenosis/*** was a statistically significant difference in national institute of health stroke scale(NIHSS)score improvement and good prognosis[the modified rankin scale(mRS)≤2]between the ACoA open group and the ACoA nonopen group on the 90th day(P<0.05).The proportion of patients with internal wind syndrome,blood stasis syndrome,Qi deficiency syndrome,and Yin deficiency syndrome in the ACoA non-open group was higher than that in the open *** In the patients with severe carotid artery stenosis/occlusion,the group with presence of anterior communicating artery had better *** syndrome elements are more complex in the group without the presence of anterior communicating *** proportion of Qi deficiency syndrome was positively correlated with the non-opening of anterior communicating *** imaging evaluation of collateral circulation can provide guidance for syndrome differentiation and treatment.

关键词： Carotid artery stenosis Anterior communicating artery(ACoA) Collateral circulation Syndrome elements Deficiency syndrome

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肺癌转移致脑膜癌病的临床分析

现代预防医学 2007年第10期34卷 1971-1972+1974页

作者：邱萌曹丹毕锋 610041 四川大学华西医院四川大学华西医院成都

[目的]分析肺癌转移致脑膜癌病的临床特点。[方法]对18例经脑脊液细胞学证实的肺癌转移致脑膜癌病患者的临床症状、脑脊液检查、影像学特点、身体状况评分、预后等临床资料进行描述性分析。[结果]原发肿瘤病理类型以支气管腺癌为主,占55... 详细信息

[目的]分析肺癌转移致脑膜癌病的临床特点。[方法]对18例经脑脊液细胞学证实的肺癌转移致脑膜癌病患者的临床症状、脑脊液检查、影像学特点、身体状况评分、预后等临床资料进行描述性分析。[结果]原发肿瘤病理类型以支气管腺癌为主,占55.6%;18例患者首发症状主要表现为头晕、头痛;单次脑脊液细胞学阳性率较低,为44.4%;分别有13例(72.2%)和11例(61.1%)患者伴有脑脊液LDH和CEA异常升高;增强CT/MRI扫描可以帮助明确诊断;患者确诊时KPS评分平均为52.5分,从起病至确诊时间范围为0.5～4个月,中位时间为1.8个月,确诊后患者生存期范围0.3～14月,中位生存期为3.6个月。[结论]脑脊液细胞学检查和增强CT/MRI扫描是目前诊断肺癌脑膜转移的最主要的方法。脑脊液LDH及CEA异常升高可作为辅助诊断指标。

关键词：肺癌脑膜癌病脑脊液细胞学

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新疆牧区高血压老人认知衰弱现状及影响因素

河北医药 2024年第12期46卷 1877-1882页

作者：吴培孟娜宋晓薇袁媛陶宁詹怀峰由淑萍新疆医科大学护理学院乌鲁木齐市830000 新疆医科大学公共卫生学院乌鲁木齐市830000 新疆维吾尔自治区乌鲁木齐县板房沟中心卫生院

目的调查新疆牧区高血压老人发生认知衰弱的现状,并探讨其影响因素。方法选取2021年5月至2022年7月乌鲁木齐县某卫生院体检和就诊的高血压老人作为研究对象,符合纳入及排除标准的共1 046例老年患者完成问卷调查及体格检查。以FRAIL衰... 详细信息

目的调查新疆牧区高血压老人发生认知衰弱的现状,并探讨其影响因素。方法选取2021年5月至2022年7月乌鲁木齐县某卫生院体检和就诊的高血压老人作为研究对象,符合纳入及排除标准的共1 046例老年患者完成问卷调查及体格检查。以FRAIL衰弱评估量表、蒙特利尔认知评估量表及临床痴呆量表进行认知衰弱的评估。结果 343例高血压老人存在认知衰弱,认知衰弱发生率为32.8%(343/1 046)。Logistic回归分析结果显示,高龄、喝咸奶茶、高血压病程长、营养不良、血脂异常及IADL受损是高血压老人发生认知衰弱的危险因素(P<0.05),吃红肉、体育锻炼是高血压老人发生认知衰弱的保护因素(P<0.05)。结论牧区高血压老人认知衰弱的发生率较高。牧区医护人员应重视该人群认知衰弱的评估,及时采取针对性的干预措施,预防或改善高血压老人的认知衰弱,以提高其生活质量。

关键词：认知衰弱高血压牧区影响因素

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Electrospun Nanocomposite Fibrous Membranes for Sustainable Face Mask Based on Triboelectric Nanogenerator with High Air Filtration Efficiency

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Advanced Fiber Materials 2023年第4期5卷 1505-1518页

作者： Yue Yang Yuchen Yang Jianying Huang Shuhui Li Zheyi meng Weilong Cai Yuekun Lai College of Chemical Engineering Fuzhou University350116 FuzhouPeople’s Republic of China Qingyuan Innovation Laboratory 362801 QuanzhouPeople’s Republic of China Department of Chemistry University College LondonLondon WC1H 0AJUK Wenzhou Institute University of Chinese Academy of ScienceZhejiang 325000 WenzhouPeople’s Republic of China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University201620 ShanghaiPeople’s Republic of China

Air pollution caused by the rapid development of industry has always been a great issue to the environment and human being’s ***,the efficient and persistent filtration to PM_(0.3) remains a great ***,a self-powered filter with micro-nano composite structure composed of polybutanediol succinate(PBS)nanofiber membrane and polyacrylonitrile(PAN)nanofiber/polystyrene(PS)microfiber hybrid mats was prepared by *** balance between pressure drop and filtration efficiency was achieved through the combination of PAN and *** addition,an arched TENG structure was created using the PAN nanofiber/PS microfiber composite mat and PBS fiber *** by respiration,the two fiber membranes with large difference in electronegativity achieved contact friction charging *** open-circuit voltage of the triboelectric nanogenerator(TENG)can reach to about 8 V,and thus the high filtration efficiency for particles was achieved by the electrostatic *** contact charging,the filtration efficiency of the fiber membrane for PM_(0.3) can reach more than 98%in harsh environments with a PM_(2.5) mass concentration of 23,000µg/m^(3),and the pressure drop is about 50 Pa,which doesn’t affect people’s normal ***,the TENG can realize self-powered supply by continuously contacting and separating the fiber membrane driven by respiration,which can ensure the long-term stability of filtration *** filter mask can maintain a high filtration efficiency(99.4%)of PM_(0.3) for 48 consecutive hours in daily environments.

关键词： Electrospinning Self-powered filter structure Triboelectric nanogenerator Air filtration