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筒体开孔机结构分析与优化设计

筒体开孔机结构分析与优化设计

作者：杨啸兰州理工大学

学位级别：硕士

随着化工业的进一步发展，特别是大型炼化厂对压力容器上所加工的法兰焊接坡口要求越来越高，如果采用传统的数控镗床进行加工，平坡口时完全可以满足要求，但是加工结构应力较好的马鞍形坡口时，普通的数控机床要想加工就要在主轴上安... 详细信息

随着化工业的进一步发展，特别是大型炼化厂对压力容器上所加工的法兰焊接坡口要求越来越高，如果采用传统的数控镗床进行加工，平坡口时完全可以满足要求，但是加工结构应力较好的马鞍形坡口时，普通的数控机床要想加工就要在主轴上安装附具（平旋盘）来完成，不光结构复杂而且加工质量难以保证，本课题所研究的筒体开孔机（SDA—01型镗孔机）是专门用于加工压力容器上法兰焊接坡口的专机，其具有加工可靠、价格相对数控镗床便宜等特点，由于是第一代机床，难免存在一些问题，因此本课题对筒体开孔机结构分析与优化设计对其进一步的推广具有重要的意义。本课题对筒体开孔机主要结构进行了分析并提出相应的优化方案，通过分析主运动传动原理，设计出用于支撑电机的支撑架，避免因电机过重导致滑枕尾部上翘，影响筒体开孔机的轴向进给，又结合实际加工出现的问题，提出了新的径向进给机构，将步进电机从主轴尾部前置在新滑座内，省去了较难加工的径向传动轴，同时解决了筒体开孔机径向润滑不利及安装调试困难等问题，然后通过分析轴向进给系统，将滑枕作为主轴组件重量减轻的目标，最后对筒体开孔机电气系统进行分析，重点介绍机床所采用的复合插补系统，本文还以轴向进给系统分析结果为基础，利用ANSYS软件对主轴与滑枕进行静、动态性能分析，同时参照现有机床的滑枕结构，对滑枕进行优化设计。本课题针对性的解决了第一代机床所存在的一些不足，使筒体开孔机（SDA—01型镗孔机）运行更加稳定、可靠，同时为第二代机床的研发打下良好的基础，相信优化后的筒体开孔机将具有更为广阔的市场。

关键词：筒体开孔机结构分析有限元方法 ANSYS Pro/E

基于AXI总线协议的SPI控制器设计与验证

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基于AXI总线协议的SPI控制器设计与验证

作者：杨晓兰州理工大学

学位级别：硕士

随着电子设计技术日新月异的发展,近年来,系统级芯片(System-on-a-Chip,So C)设计技术已经在集成电路发展的各个领域里得到广泛应用。工程师都希望自己的设计可以和更多的电子设备进行通信,因此,如今很多芯片都支持传统串行外设接口(Ser... 详细信息

随着电子设计技术日新月异的发展,近年来,系统级芯片(System-on-a-Chip,So C)设计技术已经在集成电路发展的各个领域里得到广泛应用。工程师都希望自己的设计可以和更多的电子设备进行通信,因此,如今很多芯片都支持传统串行外设接口(Serial Peripheral Interface,SPI)、通用串行总线(Universal Serial Bus,USB)等等其他电子设备接口。其中,SPI协议因其电路结构简单、通信可靠等诸多优点,在低速外部设备中得到广泛应用。本文通过研究Motorola公司的SPI协议以及ARM公司的高级可扩展接口(Advanced e Xtensible Interface,AXI)协议,设计了一种支持AXI总线传输的SPI控制器模块,该设计实现了支持多请求功能和支持乱序访问功能。论文重点介绍了该SPI控制器模块的设计原理和验证方法。首先,论文依据SPI协议基本原理给出了该SPI控制器模块的整体架构设计,并根据AXI协议端口特点对SPI控制器模块接口信号进行扩展,增加与AXI总线通信的接口,使得SPI控制器可以与AXI总线之间进行通信,能够更广泛地应用于不同的So C系统中。该SPI控制器模块由控制寄存器、扩展寄存器、数据寄存器、状态寄存器、SPI控制模块、读写模块、标识(Identification,ID)控制模块和移位寄存器等子模块构成。该SPI控制器模块支持读请求、读请求应答、写请求、写请求应答四种传输模式。其次,在完成SPI控制器模块寄存器传输级(Register Transfer Level,RTL)设计基础上,验证了若干待测功能点。基于验证方法学手册(Verification Methodology Manual,VMM)验证方法,利用System Verilog语言为该SPI控制器模块设计搭建层次化的随机验证环境,对该论文设计的SPI控制器模块进行充分验证。再次,利用Synopsys公司的Verilog模拟器编译(Verilog Compile Simulator,VCS)仿真工具对设计进行代码覆盖率统计、分析代码覆盖率并针对代码覆盖率报告结果适当添加限制条件提高代码覆盖率。对SPI控制器代码添加功能覆盖率组统计功能覆盖率。最后,对SPI控制器模块进行RTL代码综合,评估设计面积、时序、功耗。验证结果表明:本文设计的SPI控制器完全兼容SPI协议,在功能上达到了预期目标,可以灵活地应用到基于AXI总线协议的典型So C系统中,可与多种具有SPI接口的电子设备进行通信。此外,采用基于VMM方法学搭建参数可配置的随机验证环境有效提高了设计的验证效率。

关键词： AXI SPI 验证综合

Absorption characteristic of Paeoniflorin-6＇O-benzene sulfonate in an situ single-pass intestinal perfusion model

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中国药理学通报 2015年第B11期31卷 215-215页

作者： wangChun yangxiao-dan ZHOUPeng YUJun WEIWei InstitueofClinicalPharmacology AnhuiMedicalUniversityKeyLaboratoryofAnti-inflammatoryandImmuneMedicineMinistryofEducationAnhuiCollaborativeInnovationCenterofAnti-inflammatoryandImmuneMedicineHefei230032

Aim Paeoniflorin-6＇O-benzene sulfonate （CP-25） was synthesized to improve oral absorption. This study was performed to investigate absorptive behavior and mechanism of CP-25 in intestine. Methods The effects of drug concentration, intestinal segments, gender as well as ATP binding cassette （ABC） transporter inhibitors on absorption of CP-25 were studied in a situ single-pass intestinal perfusion rat model. Meanwhile, Paeoniflorin （Pae） was tested and served as control group. The concentration of tested drugs was measured by HPLC. Results The results showed intestinal absorption of CP-25 was neither segmental dependent changes nor gender difference. Transepithelial transportation would not change with increasing concentrations of CP-25, which suggest a passive transport was the main pattern of CP-25. Additionally, absorption of CP-25 was much better than that of Pae in small intestine. When compared with Pae, CP-25 gave a 1.82-fold permeability rate. Finally, the results indicated Pae was substrate of P-glycoprotein （P-gp） , but was not the substrate of breast cancer resistance protein and muhi- drug resistance associated protein 2. Among the used ABC inhibitors, the absorption rate of Pae could only be in- creased by？ P-gp inhibitor Verapamil and GF120918, while CP-25 had no remarkable alteration. Conclusion CP-25 has better absorptive features than that of Pae, which may be attributed to its lipophicity enhancement and be unaffected by P-gp efflux.

关键词： Paeoniflorin Paeoniflorin-60-benzene sulfonate single-pass intestinal peffusion P-glycoprotein

Afforestation using micro-catchment water harvesting system with microphytic crust treatment on semi-arid Loess Plateau： A preliminary result

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Journal of Forestry Research 2005年第1期16卷 9-14,i001页

作者： yangxiao-hui wangKe-qin wangBin-rui YUChun-tang ResearchInstituteofForestry ChineseAcademyofForestrySilviculturalLabofStateFo＇restryAdministrationBeijing100091P.R.China SoutheastForestryCollege Kunming650224P.R.China CollegeofSoilandWaterConservation BeijingForestryUniversityBeijing100083P.R.China ResearchInstituteofForestry ChineseAcademyofForestrySilviculturalLabofStateFo＇restryAdministrationBeijing100091P.R.China

Water harvesting is one of main measures to solve water shortage resulting from less precipitation and erratically seasonal dis- tribution in arid and semi-arid areas. Different types of anti-infiltration treatments including mechanical and chemical to micro-catchment and their runoff efficiencies had been reported. This paper, through 5 years experiment from 1992 to 1996, is aimed at studying the im- pacts of microcatchment water-harvesting system (MCWHS) with microphytic crust treatment on afforestation on semi-arid Loess Plateau. The results showed that after 3 years of crust inoculation, crust had covered majority of MCWHS and the function of water harvesting had also been demonstrated partially, there were significant difference in soil moisture of shallow soil layer in three typical spring stages be- tween crust cover and control treatments (0.05 level), and about 0.9%-6.04% increase of monthly mean soil moisture within 1m soil layer in spring of late 3 years. The impact of severe spring drought can be alleviated effectively. In the meanwhile, as crust developed on the treated surface, there are significant differences (0.05 level) for tree height (H), diameter at breast height (DBH) and diameter at ground level (DGL) at the end of the study period (1996) with the increases by 22.38%, 17.34%, and 20.49% respectively compared with the con- trol treatment. Microphytic crust, as one of biological infiltration-proof materials, may become the optimized option for revegetation in Chinese Great West Development Strategy due to its self-propagation, non-pollution to water qualities, long use duration and relatively cost effective. Further work should be focused on the selection of endemic crust species and their batch-culture in arid environment.

关键词： Afforestation Microphytic crust MCWHS Soil moisture Semi-arid Loess Plateau

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丝素蛋白基药物载体的应用研究进展

纺织学报 2023年第9期44卷 213-222页

作者：罗元泽戴梦男李蒙俞杨销王建南苏州大学纺织与服装工程学院江苏苏州215123 苏州大学纺织行业医疗健康用蚕丝制品重点实验室江苏苏州215123

为拓展和推动丝素蛋白材料在医药领域的临床应用,综述了近年来丝素蛋白在药物递送系统中的最新研究进展,重点阐述了丝素蛋白药物递送载体的种类、制备方法、主要的药物负载类型及其应用性能。通过分析发现:丝素蛋白除具有出色的生物相... 详细信息

为拓展和推动丝素蛋白材料在医药领域的临床应用,综述了近年来丝素蛋白在药物递送系统中的最新研究进展,重点阐述了丝素蛋白药物递送载体的种类、制备方法、主要的药物负载类型及其应用性能。通过分析发现:丝素蛋白除具有出色的生物相容性和可控降解性外,其大分子独特的亲疏水链结构还赋予丝素蛋白聚集态结构自组装的调控基础;以丝素蛋白为基材所构建的微球、水凝胶和微针等多种形貌的药物载体表现出高效的药物负载能力和可控的释放速率,从而达到患者减少服药次数和提高治疗效率的目的。除负载小分子化学药物,丝素蛋白载体还可改善蛋白和基因类药物易降解和半衰期短的缺点。由于丝素蛋白的这些优异特性,将其用于研制靶向与特异性药物载体可实现对不同类型疾病的针对性治疗,从而提高药物利用度和降低副作用。最后指出使用丝素蛋白作为药物载体存在的问题和重要的发展方向。

关键词：丝素蛋白药物载体生物医药制品可控释放应用性能

农机服务主体双重角色动态转变的理论逻辑与现实检验——以华北平原农机服务专业户为例

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农业经济问题 2023年第10期 32-46页

作者：魏素豪卢洋啸吉林大学行政学院长春130012 吉林农业大学经济管理学院长春130118

兼具生产与服务功能的农机服务主体是推动中国农业机械化与现代化进程的重要载体。本文结合华北平原农业机械化的调研数据,以农机服务专业户为例,考察了农机服务主体双重角色转变的内在理论逻辑。研究发现,农机作业服务市场竞争与交易... 详细信息

兼具生产与服务功能的农机服务主体是推动中国农业机械化与现代化进程的重要载体。本文结合华北平原农业机械化的调研数据,以农机服务专业户为例,考察了农机服务主体双重角色转变的内在理论逻辑。研究发现,农机作业服务市场竞争与交易成本的外部困境,引致农机服务主体服务半径收缩、服务面积与收益同步下降,出现农机和劳动时间的同时闲置;人力资本专用和实物资产专用性的内部矛盾,增加了农机服务主体转入其他行业的粘性,其本身在经营农业方面具有人力资本和机械装备的比较优势;在外部困境与内部矛盾的双重约束下,农机服务主体角色从服务供给主体转变为租地自营兼具对外服务的农地规模经营主体,实现土地规模化与服务规模化的交融发展。本文为思考中国式农业规模化经营的新路径提供了重要线索。

关键词：农机服务主体角色转变市场竞争资产专用性交易成本

Mitochondrial dysfunction, mitophagy and tissue fibrosis therapy

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中国药理学通报 2015年第B11期31卷 96-96页

作者： CHENXiao-hong LIUTao yangxiao-hong CHENBo wangFang-qin DepartmentofPharmacology ThirdMilitaryMedicalUniversityChongqing400038

Current pharmacological therapies used in clinical practice for individuals with cardiac, hepatic, renal or pulmonary fibrosis do not show desirable effects; therefore, new targets of therapy are urgently required. Mitochon- dria play pivotal role in energy production, metabolism, serving as storage tanks of calcium ions and cell fate deter- mination. Recent results of our experiments and other authors＇ studies suggest that the electron transport chain dys- function, electron leakage increasing, the accumulation of fragmented mitochondria, and the impairment in the mi- tophagy system contribute to pathogenesis of tissue fibrosis. Mitochondria targeting compounds exert promise in trea- ring and attenuating the progress of these diseases, indicating potential strategies to target mitochondria in the treat- ment of tissue fibrosis.

关键词： tissue fibrosis mitochondrial pharmacology mitochondrial target mitochondrial dysfunction mitoph-agy electron transport chain ( ETC

Effect of 6＇-acetylpaeoniflorin on dinitrochlorobenzene induced allergic contact dermatitis in BALB/c mice

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中国药理学通报 2015年第B11期31卷 35-35页

作者： CHOUPeng wangChun yangxiao-dan JIAXiao-yi YUJun JAMESAsenso WEIWei InstituteofClinicalPharmacology AnhuiMedicalUniversityKeyLaboratoryofAnti-inflammatoryandImmuneMedicineMinistryofEducationAnhuiCollaborativeInnovationCenterofAnti-inflammatoryandImmuneMedicineHefei230032

Aim The present study aimed to investigate anti-inflammatory activity of 6-AP on murine model of aller- gic contact dermatitis （ACD）. Methods 6＇-acetylpaeoniflorin （6-AP） was synthesized from paeoniflorin （Pae） via acetylation and the structure was characterized by 1H-NMR, 13C-NMR and EI-MS. ACD model was established by repeated application of dinitrochlorobenzene （DNCB） to induce skin immune inflammation. The mice were oral- ly administered 6-AP （35, 70, 140 mg. kg-1 ·d^-l）, Pae （70 rag. kg-1·d^-1） and prednisone （Pre, 5 rag. kg^- 1· d^-1 ） from day 1 to day 7 after Cutaneous inflammation was evaluated by ear swelling and histological exami- nation. Splenocyte proliferation was assayed by the 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyl-2H tetrazolium bromide assay. The cytokine production in the splenocytes was measured by enzyme-linked immunosorbent assay. Results Topical application of DNCB to the skin provoked obvious swelling and inflammatory cell infiltration. 6- AP significantly inhibited ear swelling, decreased inflammatory cell infiltration and epidermal keratinization. Ad- dtionally, 6-AP obviously alleviated the hyperplasia of red pulp and germinal center （GC） appearance, decreased spleen index, decreased spleen index, and inhibited splenocyte proliferation in ACD model, compared to that of Pae. Further, the study indicated that 6-AP treatment could increase IL-10 level, while reduce IL-17 level in splenocytes simultaneously. The correlation analysis displayed significantly positive correlations between IL-17 level and the severity of skin inflammation, while negative correlations between IL-10 level and skin inflammation. Con- clusion 6-AP has a significantly higher anti-inflammatory effect than Pae, and it may be a useful treatment for ACD.

关键词： 6'-acetylpaeoniflorin paeoniflorin allergic contact dermatitis anti-inflammatory activity

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聚吡咯/丝素导电纳米纤维膜的制备及其性能

纺织学报 2022年第10期43卷 16-23页

作者：俞杨销李枫王煜煜王善龙王建南许建梅苏州大学纺织与服装工程学院江苏苏州215021 苏州大学纺织行业医疗健康用蚕丝制品重点实验室江苏苏州215123

为开发具有一定导电性的组织再生材料,采用静电纺丝法制备了丝素纳米纤维膜,通过原位氧化聚合获得了聚吡咯/丝素导电性纳米纤维膜,探究了纺丝参数对纳米纤维膜表面形貌的影响,利用四探针测试仪测试了纳米纤维膜的导电性,借助红外光谱仪... 详细信息

为开发具有一定导电性的组织再生材料,采用静电纺丝法制备了丝素纳米纤维膜,通过原位氧化聚合获得了聚吡咯/丝素导电性纳米纤维膜,探究了纺丝参数对纳米纤维膜表面形貌的影响,利用四探针测试仪测试了纳米纤维膜的导电性,借助红外光谱仪对纳米纤维膜化学结构进行了表征。结果表明:在质量浓度为0.16 g/mL,推注速度为0.2 mL/h,电压为20 kV,滚筒转速为1000 r/min的条件下,制备的丝素纳米纤维膜表面规整,珠状物少,纤维平均直径为(520.70±140.81)nm;在吡咯单体浓度为0.3 mol/L,掺杂剂浓度为0.3 mol/L,吡咯单体与FeCl_(3)的量比为1∶2,聚合时间为6 h条件下,制备的聚吡咯/丝素导电性纳米纤维膜保留了丝素纳米纤维膜原有的纳米纤维结构,电导率达到(0.44±0.07)S/cm。

关键词：聚吡咯丝素蛋白静电纺丝原位氧化聚合导电纳米纤维膜