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现代城市环境工程地质研究的关键技术与问题探讨

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智能城市应用 2024年第4期7卷 117-119页

作者：魏娜张东生贺纪国山东正元冶达环境科技有限公司山东济南250101 山东正元地质资源勘查有限责任公司山东济南250101

伴随着我国城市化进程的加快,自然工程活动频繁出现,引发了城乡自然地质开发改造领域的一系列重大变化。因此,在城市环境中对环境工程地质等问题进行系统研究和调查将成为工程人员和居民关注的焦点。基于此,文章就城市环境工程地质研究... 详细信息

伴随着我国城市化进程的加快,自然工程活动频繁出现,引发了城乡自然地质开发改造领域的一系列重大变化。因此,在城市环境中对环境工程地质等问题进行系统研究和调查将成为工程人员和居民关注的焦点。基于此,文章就城市环境工程地质研究的关键技术以及相关的问题进行分析探究,供参考。

关键词：城市环境工程地质研究问题分析关键技术

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行波型方孔定子超声电机结构设计与性能分析

压电与声光 2023年第3期45卷 408-413页

作者：张东升张景阳中国民航大学航空工程学院天津300300

该文提出了一种新型的方孔定子行波超声电机,并进行了参数设计、仿真分析和实验研究。定子由1个方孔金属体和4块压电陶瓷片组成,通过与直径大于定子内边长的转子配合发生弹性变形,从而对转子产生预压力,便于驱动。利用有限元软件对定子... 详细信息

该文提出了一种新型的方孔定子行波超声电机,并进行了参数设计、仿真分析和实验研究。定子由1个方孔金属体和4块压电陶瓷片组成,通过与直径大于定子内边长的转子配合发生弹性变形,从而对转子产生预压力,便于驱动。利用有限元软件对定子进行模态分析,选择第三阶模态作为工作模态,得到定子最大振幅与激励频率、电压、壁厚、边长及圆角半径的关系,并研究了频率、电压及预压力对转子输出特性的影响。制作了实体样机并测试了其输出特性,测试表明,当电压为100 V、激励频率为31.5 kHz时,其空载转速为215 r/min,堵转力矩达到1.58 mN·m。

关键词：行波型超声电机方孔定子工作模态输出特性

Host-guest interaction of β-cyclodextrin with isomeric ursolic acid and oleanolic acid:physicochemical characterization and molecular modeling study

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The Journal of Biomedical Research 2017年第5期31卷 395-407页

作者： Yuan Huang Peng Quan Yongwei Wang dongsheng zhang Mingwan zhang Rui Li Nan Jiang Department of Pharmacy Affiliated Wuxi Peoples HospitalNanjing Medical University Department of Pharmaceutical Sciences Shenyang Pharmaceutical University School of Pharmacy Nanjing Medical University Department of Colorectal Surgery The First Affiliated Hospital of Nanjing Medical University

Ursolic acid(UA) and oleanolic acid(OA) are insoluble drugs. The objective of this study was to encapsulate them into β-cyclodextrin(β-CD) and compare the solubility and intermolecular force of β-CD with the two isomeric triterpenic acids. The host-guest interaction was explored in liquid and solid state by ultraviolet-visible absorption,1H NMR, phase solubility analysis, and differential scanning calorimetry, X-ray powder diffractometry, and molecular modeling studies. Both experimental and theoretical studies revealed that β-CD formed 1: 1 water soluble inclusion complexes and the complexation process was naturally favorable. In addition, the overall results suggested that ring E with a carboxyl group of the drug was encapsulated into the hydrophobic CD nanocavity. Therefore, a clear different inclusion behavior was observed, and UA exhibited better affinity to β-CD compared with OA in various media due to little steric interference, which was beneficial to form stable inclusion complex with β-CD and increase its water solubility effectively.

关键词： β-cyclodextrin oleanolic acid ursolic acid host-guest interaction molecular modeling

Prototype of multi-filament electron curtain accelerator

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Nuclear Science and Techniques 2013年第B12期24卷 1-4页

作者： LI Guohua TANG Huaping LIU Jinsheng zhang Huayi LIU Yaohong zhang dongsheng HE Yu LI Jian GUAN Weiqiang Division of Accelerator Technology Nuctech Co. Ltd Beijing 100084 China Department of Engineering Physics Tsinghua University Beijing 100084 China

In this paper, we present a prototype of electron curtain accelerator with 200 kV high voltage and an average beam current around 20 mA with beam width about 600 mm. Several physical and mechanical design of this facility is discussed in detail thoroughly, in conjunction with 3D software modeling and simulation. And some efforts to modulate cathode structure have been done to improve the electron beam uniformity effectively. © 2013, Science Press. All rights reserved.

关键词：电子帘加速器原型机械设计软件建模阴极结构高电压均匀性电子束

Sex Disparities in the Association of Blood Pressure Parameters and Arterial Sclerosis Risk

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Biomedical and Environmental Sciences 2024年第7期37卷 795-799页

作者： Dongdong zhang Weiling Chen Minqi Gu Xi Li Yuying Wu Xueru Fu Ping Tang Fulan Hu Jing Li Xizhuo Sun dongsheng Hu Ming zhang Department of General Practice The Affiliated Luohu Hospital of Shenzhen University Medical SchoolShenzhen 518060GuangdongChina Department of Allergy and Clinical Immunology State Key Laboratory of Respiratory DiseaseNational Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory Healththe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510120GuangdongChina Department of Biostatistics and Epidemiology School of Public HealthShenzhen University Medical SchoolShenzhen 518060GuangdongChina

Cardiovascular disease(CVD)is the leading cause of death worldwide[1].Arterial sclerosis(AS)and hypertension are the main risk factors and pathological bases of *** pulse wave velocity(PWV)measurements could reflect early progression of *** on the structure-function properties of the vascular wall and hemodynamics,strong evidence suggests that any increase in blood pressure levels can mechanically impair the ability of the endothelium to maintain vascular homeostasis[2].High levels of blood pressure parameters,such as systolic blood pressure(SBP),diastolic blood pressure(DBP),pulse pressure(PP),and mean arterial pressure(MAP)have been identified as essential risk biomarkers for atherosclerosis.

关键词： Blood Arterial atherosclerosis

Ag/reduced graphene oxide(RGO) nanocomposites for detection of TNT

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北京化工大学学报（自然科学版） 2019年第5期46卷 8-15页

作者： DONG JunYing CHEN DongLiang CHEN Jing YI Rui zhang dongsheng XU Peng College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029 CAS Key Laboratory of Standardization and Measurement for Nanotechnology National Center for Nanoscience and TechnologyBeijing 100090China

The modified Hummers method was employed to generate graphene oxide,and Ag /reduced graphene oxide (RGO) nanocomposites were synthesized at different temperatures by using sodium citrate as the reductant. Scanning electron microscopy (SEM),transmission electron microscopy (TEM),X-ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were employed to characterize the reaction products. The results indicate that RGO has been synthesized successfully,and Ag particles are distributed evenly on the surface of *** RGO prepared at a reaction temperature of 120℃ shows the best surface-enhanced Raman scattering (SERS) *** Ag /RGO nanocomposites modified by 10^- 5 mol /L 4-aminothiophenol (PATP) successfully detect a 10^- 5 mol /L 2,4,6-trinitrotoluene (TNT) alcohol solution.

关键词： sodium citrate reduced graphene oxide Ag /RGO surface-enhanced Raman scattering (SERS) trinitrotoluene(TNT)

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弯曲损耗对分布式光纤拉曼测温解调的影响

激光与光电子学进展 2023年第5期60卷 92-96页

作者：申文博张东生武汉理工大学机械工程学院湖北武汉430070 武汉理工大学光纤传感技术国家工程实验室湖北武汉430070

研究了弯曲损耗对分布式光纤拉曼测温解调的影响,从理论上分析了单路解调算法和双路解调算法的解调原理,并通过实验验证了两种解调算法对存在多处弯曲损耗光纤的温度解调可行性。实验结果表明,两种解调算法均可适用于已发生弯曲损耗光... 详细信息

研究了弯曲损耗对分布式光纤拉曼测温解调的影响,从理论上分析了单路解调算法和双路解调算法的解调原理,并通过实验验证了两种解调算法对存在多处弯曲损耗光纤的温度解调可行性。实验结果表明,两种解调算法均可适用于已发生弯曲损耗光纤的温度解调,但对于发生弯曲损耗位置附近的光纤,单路解调算法的准确度和波动性优于双路解调算法。

关键词：光纤光学分布式光纤测温系统温度解调算法光纤损耗

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结直肠癌微卫星不稳定性检测的应用与挑战

中华消化外科杂志 2023年第6期22卷 703-709页

作者：孙跃明张冬生南京医科大学第一附属医院结直肠外科、南京医科大学结直肠病研究所南京210029

结直肠癌是常见的消化道恶性肿瘤之一,我国结直肠癌的发病率及死亡率仍呈上升趋势。探究结直肠癌发生、发展的分子机制具有重要意义。微卫星是遍布于基因组中的短串联重复序列,微卫星不稳定性(MSI)检测在结直肠癌的临床诊断与治疗中具... 详细信息

结直肠癌是常见的消化道恶性肿瘤之一,我国结直肠癌的发病率及死亡率仍呈上升趋势。探究结直肠癌发生、发展的分子机制具有重要意义。微卫星是遍布于基因组中的短串联重复序列,微卫星不稳定性(MSI)检测在结直肠癌的临床诊断与治疗中具有重要价值。MSI检测是Lynch综合征筛查的重要方法。对于Ⅱ期结直肠癌患者,MSI状态是术后复发的影响因素,亦是辅助治疗的重要参考依据。对于Ⅳ期结直肠癌患者,MSI状态是筛查免疫检查点抑制剂适用人群的重要指标。然而,MSI的应用仍然存在一系列问题。MSI检测方法并未完全统一,MSI检测对象的要求具有普遍性但缺乏精准性,MSI对预后的预测作用不足,MSI对化疗、免疫治疗疗效的判断作用不足。此外,随着其他相关分子靶标,如程序性细胞死亡受体1、程序性细胞死亡受体配体1、肿瘤突变负荷、免疫评分等的临床应用,MSI在结直肠癌中的应用价值面临挑战,有待更多研究深入挖掘。笔者就MSI检测及应用存在的问题进行探讨,旨在为临床实践提供参考。

关键词：结肠肿瘤直肠肿瘤微卫星不稳定性诊断治疗挑战

Micro-and Nano-structure Characterization of Isotropic Pyrocarbon Obtained via Chemical Vapor Deposition in Hot Wall Reactor

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Journal of Materials Science & Technology 2010年第12期26卷 1133-1138页

作者： Kezhi Li,dongsheng zhang,Lingjun Guo and Hejun Li State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi an 710072,China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 China

The hot wall reactor was used to deposit isotropic pyrocarbon. The density of the product was measured by Archimedes method. The fracture morphology and texture of the product were investigated by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Raman spectroscopy was also applied to characterizing the structure of the product. The results show that the density of the product is about 1.31 g/cm^3. The pyrocarbon consists of granular particles with the size of about 1.5 μm under SEM images. Under TEM images, the pyrocarbon is composed of irregular grains and onion-like particles are also detected. The orientation angle （180 deg.） of pyrocarbon reveals its isotropic character. The ID/IG ratio in Raman spectrum is about 1.2, indicating the isotropic feature of the product qualitatively.

关键词： Isotropic pyrocarbon Chemical vapor deposition Structure characterization Onion-like pyrocarbon