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Search Results: 1 - 10 of 34392 matches for " 邵亮 "
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图书馆基金会——发展我国图书馆事业的措施之一

图书情报工作 , 1996,
Abstract: ?阐述了基金会的社会作用,提出我国要加快发展图书馆事业,应成立图书馆基金会,并对图书馆基金会的任务、方法和基金来源作了探讨
高架轻轨箱梁噪声辐射现场实测分析
Measurement of noise radiated from box girder of elevated light rail transit

,
- , 2018, DOI: 10.16300/j.cnki.1000-3630.2018.01.014
Abstract: 对武汉轻轨一号线某高架段25 m跨单箱单室预应力钢筋混凝土简支箱梁的噪声辐射进行了现场测试。将采集的噪声信号利用快速傅里叶变换技术通过相干函数进行一定程度的净化,从而获得真实的结构辐射噪声。绘制了箱梁结构表面辐射声压级等值线图。比较分析了综合噪声和结构辐射噪声的A声级。分析结果表明:近轨时箱梁结构各部位的辐射噪声明显大于远轨时箱梁结构各部位的辐射噪声。在近轨和远轨两种工况下,底板和翼缘的辐射噪声都大于腹板。箱梁各部位的辐射声压级在跨长方向和桥宽度方向上都表现出非单一的变化规律,需结合列车运行工况具体分析。轻轨箱梁结构辐射噪声级在61~66 dB(A)之间,实际工程中为了获得真实的结构辐射噪声级需将测得的综合噪声级减去约2 dB(A)(背景噪声影响)。实测分析结果可让工程技术人员了解箱梁噪声辐射情况,为后期箱梁的降噪设计提供参考依据。
In an elevated section of Wuhan light rail Line 1, a field test of the noise radiation has been made for the prestressed reinforced concrete simply supported box girder with a 25 m span of single box and single chamber. By using the Fast Fourier Transform (FFT) technique, the noise signal is purified to some extent by the coherence function so that the real structural radiation noise can be acquired. The contour maps of radiated sound pressure level from the surface of box girder are drawn and the A-weighted sound pressure levels of overall noise and structural radiation noise are compared and analyzed. The results show that for near rail the radiation noise from each part of box girder is significantly greater than that for distant rail. In these two conditions of near rail and distant rail, the radiation noises from bottom plate and flange plate are all greater than from web. The radiated sound pressure levels at diffident parts of box girder show different changing rules along the long span and bridge width, which should be analyzed according to the operation conditions of the train. The radiation noise of light rail box girder is between 61 dB (A) and 66 dB (A), and the 2 dB (A) influence of background noise should be deducted from comprehensive noise in order to obtain real structural radiation noise. The analysis of the measurement result can help engineers comprehend the noise radiation from the box girder, and provides a reference for the noise reduction design of the box girder.
宁波离岸服务外包发展存在问题与对策研究
Research on Problems and Countermeasures of Ningbo’s Offshore Service Outsourcing Development
 [PDF]

姜丽花, 林承, 金菊
Business and Globalization (BGlo) , 2015, DOI: 10.12677/BGlo.2015.33003
Abstract:
发展服务外包对宁波推进传统产业转型升级、优化开放型经济模式、推动人口结构调整、提升城市竞争力等具有重大意义。宁波服务外包产业后发崛起,但与先进城市相比具有较大差距。本文梳理宁波离岸服务外包发展现状,深入分析宁波离岸服务外包发展存在问题,重点提出加快宁波离岸服务外包发展的对策。
The developing service outsourcing is of great significance for Ningbo to transform and upgrade the traditional industries, optimize the open economy model, promote the adjustment of population structure, and enhance the city competitiveness. Ningbo’s service outsourcing industry has risen sharply, but it still has a large gap compared with the advanced cities. This paper has combed the developing situation of the Ningbo’s offshore service outsourcing, analyzed the problems of development of Ningbo’s offshore service outsourcing, and proposed the countermeasures to accelerate the development of offshore service outsourcing in Ningbo.
多点地震输入的反应谱法研究
,寿磊
工程力学 , 2014, DOI: 10.6052/j.issn.1000-4750.2013.06.0559
Abstract: 提出了一种计算多点输入下结构最大地震内力的新反应谱法(MRSM-AD)。不同于以往的多点输入反应谱法,这种方法不再将结构的绝对位移反应分解成拟静力和动力分量,而是直接利用基于结构绝对位移反应的动力方程进行反应谱理论的分析,简化了多点输入反应谱法中的组合规则,提高了结构计算分析的效率。比较了结构算例的时程法计算结果和MRSM-AD法的分析结果,验证了MRSM-AD法的正确性。
快速成型尼龙66的非等温结晶动力学分析
董学,露露
- , 2017,
Abstract: 采用差示扫描量热仪(DSC)考察快速成型尼龙66的非等温结晶行为.分别用Jeziomy方程、Ozawa方程和Mo Zhishen方程对快速成型尼龙66的非等温结晶动力学行为进行比较分析.Jeziomy方程分析结果表明,快速成型尼龙66的非等温结晶分为主结晶期和后结晶期两个过程,主结晶期和后结晶期的Avrami指数n和结晶速率常数Zc不同,表明快速成型尼龙66的主结晶期和后结晶期的成核机理和晶体生长方式不同.Ozawa方程不适合处理快速成型尼龙66的结晶行为,Mo Zhishen方程可以有效描述快速成型尼龙66的非等温结晶行为.
基于涡方法生成大涡模拟进口条件的数值计算
Generation of unsteady inflow conditions for compressible LES with a modified vortex method

谢宝林,
- , 2015, DOI: 10.13700/j.bh.1001-5965.2014.0281
Abstract: 摘要 探索改进涡方法来生成大涡模拟的非定常进口条件.改进方法中,为了避免局部漩涡数量过多或者过少,采用密度分布方式放置漩涡场.并用Langevin方程控制漩涡运动,模拟实验方法中的蜂窝器,使改进后的涡方法生成的脉动速度场更加符合湍流的特征.在已知雷诺平均的流场结果下,利用涡方法产生漩涡场,进而生成能满足大涡模拟所需要的非定常进口流场.为了检验改进后的涡方法在生成脉动速度过程中的效果,在槽道中进行了对比数值试验,并借助于直接数值模拟数据做对比,对比分析槽道进出口的平均速度、涡量以及雷诺应力统计,证明改进后的涡方法在生成大涡模拟进口条件下是非常有效的.
Abstract: This article is to explore and modify vortex method to generate large eddy simulation (LES) inlet condition. In the modification, a density distribution of vortex which can avoid unreasonable vortex quantity in local place was used. The movement of vortex was controlled by Langevin equation, which mimics the active grid turbulence so as to generate an unsteady flow field which is more like the real turbulence. Knowing the results of Reynolds-averaged Navier-Stokes equations (RANS) and reconstructing the turbulence by vortex method (VM), the method was tested in the experimental channel. The statistical results of both inlet and outlet of the channel were given, which include the mean velocity, the vorticity and the Reynolds stress. By analyzing the generated field with the reference of direct numerical simulation (DNS) results and comparing with the results of original method, during the development of turbulence in the channel, it shows that the modified vortex method is viable and cost-effective for generating unsteady inflow condition for LES.
纳米银诱导的以免疫毒性为主的早期全身毒性研究
Silver Nanoparticles Induced Immunotoxicity-Based Early Systemic Toxicity
 [PDF]

安良, 王志杰,, 徐丽明
Immunology Studies (IS) , 2014, DOI: 10.12677/IS.2014.24006
Abstract:
目的:考察纳米银对大鼠免疫系统的影响以及其他早期全身毒性反应;同时考察纳米银在体外对淋巴细胞炎性因子和免疫因子释放的影响。通过体内外试验的综合研究考察纳米银的潜在免疫系统毒性。方法:SD大鼠经连续灌胃给入低剂量(1 mg/kg)和高剂量(10 mg/kg)纳米银溶液,生理盐水溶液(对照组)。于首次给入后2小时、连续给入7天、14天及停止给入14天后分别处死大鼠,然后进行大鼠体内各脏器银元素定量测定和病理学分析、血液学及血液生化检测、相关免疫因子的检测。体外试验中,在纳米银暴露或非暴露条件下,将淋巴细胞于含或不含脂多糖的培养液中培养24小时,分析IL-6、IL-4、IgG、IgE等的含量,以考察纳米银引起的免疫系统毒性。结果和讨论:纳米银暴露组显示纳米银剂量、时间依存性的在大鼠血液及脏器组织内蓄积。与对照组相比,经口给入高剂量纳米银(10 mg/Kg)引起了大鼠淋巴细胞IgE、IgG与IL-4的显著增加;高、低剂量组给入纳米银14天停止给入14天后,血清IL-6水平与B细胞CD45RA+水平均显著增加。虽然经纳米银灌胃后大鼠组织病理学检查未发现显著的病理改变,但血糖和碱性磷酸酶的升高提示有胰脏和肝脏的损伤。血常规显示血液内银在低浓度时刺激炎性细胞反应性增加;而高浓度时则诱导细胞毒性,抑制了淋巴细胞的正常生长。在体外不同浓度纳米银(0.5 μg/mL,5 μg/mL)作用下,LPS诱导的淋巴细胞分泌IgG和IL-6显著减少。综合体内外实验结果表明,本研究所用的纳米银主要引起了大鼠以Th2型免疫毒性为主的早期全身毒性。
Objective: To investigate the effects on immune system and other systemic toxicity of silver nano-particles (SNPs) in rats by oral exposure, and combined an in vitro study of SNPs on the release of inflammatory cytokines and immune factors in lymphocytes, to get a better understanding about potential immunotoxicity of silver nanoparticles. Methods: SD rats were orally administrated with low-dose (1 mg/kg) and high-dose (10 mg/kg) of SNPs and saline (control) respectively, and the organ and blood samples were harvested after 2 hrs (n = 9), 7 days (n = 18), 14 days (n = 18) ex-posure and14 days of post-exposure (n = 9) for determination of silver content, hematology, blood biochemistry, and immune factor assessment. Lymphocytes were incubated with or without lipo-polysaccharide in the presence or absence of silver nanoparticles for 24 hours in vitro. And IL-6, IL-4, IgG and IgE of cell culture supernatants were analyzed by ELISA. Results and Discussion: SNPs exposure group showed SNPs accumulated time-dose dependently in blood and organs of rats. The IgG (14 days), IgE (14 days) and IL-4 (7 days) of rats after 10 mg/kg SNPs exposure were signifi-cantly increased, and IL-6 and CD45RA+ (B cells) at 14 days post-exposure of SNPs were obviously increased, compared with that in control. But we did not find significant pathological changes. The rise of glucose and ALP suggested damage of pancreas and liver of rats after SNPs oral administra-tion. Low concentration silver in blood increased inflammatory cells in response to the stimuli by blood examination, while high concentration induced cytotoxicity which inhibited the normal growth of lymphocyte. Secretion of IgG and IL-6 induced by LPS of lymphocytes in low-dose and high-dose (0.5 μg/ml, 5 μg/ml) SNPs exposure was inhibited in vitro. In conclusion, our study showed that silver
Reviews on Main Evaluation Systems for Chinese Scientific Journals
近年来我国科技期刊的主要评价体系综述

陈嘉伟,
中国科技期刊研究 , 2010,
Abstract: 科技期刊学术评价体系正日益受到人们的关注,科学的期刊评价体系有利于对期刊的学术水平作出客观、全面和正确的评价,从而有利于引导和促进我国科技期刊的良性发展。本文对我国目前新兴的科技期刊学术评价体系的应用进展进行综述,并提出构建科学的科技期刊学术评价体系的思路。
含穿透裂纹岩石的高频疲劳特性研究
周有成,陈有,
工程力学 , 2011,
Abstract: 该文以高强度白水泥为模拟材料,对含预置不同数目穿透裂纹的岩石进行了单轴压缩试验以及高频疲劳单轴压缩试验研究。该文充分考虑了裂纹对岩石试块宏观力学性能的影响,描述了裂纹扩展的规律,得到了含穿透裂纹的岩石材料的S-lgN曲线和考虑裂纹相互作用的疲劳方程。
水饱和混凝土单轴压缩弹塑性损伤本构模型
陈有,,周有成
工程力学 , 2011,
Abstract: 多孔多相的饱和混凝土中,孔隙自由水对混凝土的力学特性有显著的影响。该文基于损伤力学基本原理建立了单轴压缩条件下水饱和混凝土的弹塑性损伤本构模型,并结合太沙基“有效应力原理”,认为材料的损伤是由本体有效应力和结构有效应力引起的,根据应力平衡条件得出了两种有效应力下的应力关系方程,并在此基础上建立了水饱和混凝土的单轴压缩损伤演化方程。
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