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CMB

CMB的相关文献在1981年到2021年内共计93篇,主要集中在环境污染及其防治、天文学、水路运输 等领域,其中期刊论文87篇、会议论文1篇、专利文献5篇;相关期刊60种,包括中关村、科学文化评论、高等教育发展研究等; 相关会议1种,包括中国通信学会第五届学术年会等;CMB的相关文献由177位作者贡献,包括吴建会、冯银厂、朱坦等。

CMB—发文量

期刊论文>

论文:87 占比:93.55%

会议论文>

论文:1 占比:1.08%

专利文献>

论文:5 占比:5.38%

总计:93篇

CMB—发文趋势图

CMB

-研究学者

  • 吴建会
  • 冯银厂
  • 朱坦
  • Eugene Terry Tatum
  • 吕爱华
  • 张克潭
  • 彭林
  • 毕晓辉
  • 刘雁
  • 孙通
  • 期刊论文
  • 会议论文
  • 专利文献

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    • 陈健容; 刘祥治; 陈仲良; 邱创嘉; 赖喜春
    • 摘要: 目的:对比急性缺血性脑卒中(AIS)患者应用磁共振成像(MRI)序列中一般使用的常规序列与近年兴起的MRI技术-磁敏感加权成像(susceptibility weighted imaging,SWI)诊断脑微出血(CMB)的临床价值.方法:对我院收治的45例AIS患者临床资料进行回顾性分析,所有患者都予以MRI常规序列与SWI扫描,比较MRI不同序列检测CMB的影像学表现特点,并记录CMB病灶在不同序列中的检出情况.结果:SWI检出CMB病灶数量最多,为68个;其次为DWI序列,检出36个CMB病灶;较为DWI序列次之T2WI FLAIR序列,亦检出24个CMB病灶;而T2WI序列检出CMB病灶10个;T1WI序列对于CMB病灶检出率最低,为4个.其中,CMB病灶多数位于基底节区.结论:相对MRI常规序列而言,SWI对于AIS患者中的CMB病灶检出率具有更高的影像诊断价值.
    • 高雪倩; 吴建会; 张会涛; 张文慧; 戴启立; 宫攀
    • 摘要: 采集并分析了武汉市机动车尾气源PM2.5样品,并于2019年10月18~27日采集了武汉市不同路边微环境(市区路边、环线路边、环境背景点)PM2.5样品并分析其化学组分特征,利用化学质量平衡模型(CMB)解析评估了机动车尾气对城市不同路边微环境PM2.5的贡献.结果 表明,机动车尾气成分谱以OC和EC为主,汽油车OC质量分数约为柴油车的1.14倍,柴油车EC质量分数是汽油车的1.08倍.路边碳组分主要来源于机动车尾气,其中OC浓度在市区路边最高,EC浓度在环线路边最高;市区路边NO3和NH4+浓度较高,与二次转化有关;环线路边Fe、Si、Al质量浓度高于市区路边.CMB来源解析结果显示,机动车尾气源是环线路边、市区路边微环境的主要来源,分担率为35.20%和38.89%,是环境背景点的2倍左右.不同路边微环境污染源贡献差异明显,与环线路边相比,市区路边机动车尾气源与二次来源均相对较高,而扬尘源贡献低于环线路边.
    • 张军; 张蕾; 姬亚芹; 赵静琦; 王士宝; 李越洋; 张伟
    • 摘要: 为研究盘锦市全年大气PM2.5的污染特征和来源,于2016年4月至2017年1月采集盘锦市3个点位受体PM2.5以及污染源样品,通过OC/EC比值法,富集因子法,CMB受体模型等对PM2.5进行污染特征及来源分析.结果表明,盘锦市PM2.5浓度年均值超过环境空气质量标准(GB 3095-2012)二级标准;硫氧化率(SOR)和氮氧化率(NOR)的均值均大于0.10,说明SO42-、NO3-主要由SO2和NOx转化而来.OC/EC均值大于2.0,说明盘锦市大气中可能存在二次污染,富集因子分析可知盘锦市PM2.5中14种元素不同程度受到人为因素的影响;盘锦市污染源谱特征明显,Si元素为扬尘源中含量最高的组分,建筑水泥尘与堆场扬尘中Ca元素的含量明显;煤烟尘中SO42-含量最高;餐饮油烟以OC为主;石化尘和移动源以EC、OC为主;生物质燃烧源以OC和K为主;通过CMB进行来源解析得出盘锦市全年PM2.5主要来源于煤烟尘、扬尘以及移动源.%In order to study the characteristics and source of atmospheric PM2.5 of Panjin, PM2.5 samples were collected at three sites from April 2016 to January 2017. Pollution characteristics and source of PM2.5 were analyzed by OC/EC ratio method, enrichment factor method and CMB receptor model. The results showed that annual PM2.5 concentration exceeded the ambient air quality standard (GB3095-2012). The mean values of SOR and NOR were all higher than 0.10, indicating that SO42- and NO3 - were mainly converted from SO2 and NOx. OC/EC ratios were more than 2.0 during the sampling periods, indicating that there was secondary pollution. Analysis of enrichment factors showed that many trace elements in PM2.5 were affected by humans. Characteristics of the pollution source profile of Panjin City were obvious,and Si was the component with the highest content in fugitive dust. For cement dust and yard dust, Ca was the most abundant specie. The major species in coal combustion was SO42-. Cooking source mainly based on OC, OC and EC were the main species in mobile source and petrochemical dust. OC and K were the main components of biomass burning. Through CMB method, PM2.5 in Panjin City were mainly derived from coal combustion, fugitive dust and mobile source.
    • XU Chenxi; CHEN Junhui; HAN Li; WANG Jiqin
    • 摘要: 为了解宜宾市冬季VOCs(volatile organic compounds,挥发性有机物)污染特征,于2016年12月选取宜宾市2个国控环境监测点位,采集冬季环境空气VOCs样品,利用三级冷阱预浓缩仪-气相色谱质谱联用仪(GC-MS)测定大气中89种VOCs物种,分析VOCs体积分数及其物种组成情况,并对其主要来源进行识别.结果表明:宜宾市区冬季环境空气中Φ(VOCs)平均值为35.10×10-9,Φ(VOCs)最高值和最低值分别为67.34×10-9、20.58×10-9;监测VOCs物种类别中芳香烃占比最高,其次为烷烃、卤代烃;体积分数较大的VOCs物种主要为苯、甲苯、氯甲烷、二氯甲烷、异丁烷、异丙醇、正丁烷等.CMB(化学质量平衡)模型源解析宜宾市冬季环境空气VOCs的六大主要贡献源分别为移动源、油气挥发源、溶剂使用源、工艺过程源、生物质燃烧源和其他源.以2015年为基准年,利用排放因子法对宜宾市VOCs进行排放量计算发现,宜宾市VOCs年排放量为39.54×103 t,其中,工艺过程源、溶剂使用源、移动源、化石燃料燃烧源的贡献率分别为35.5%、24.5%、28.9%、8.0%.研究显示,对宜宾市冬季环境空气中VOCs贡献率较大的污染源分别为移动源、溶剂使用源、工艺过程源等.
    • 摘要: 1月8日,比利时CMB表示,该集团计划于2023年推出全球第1艘氢动力散货船,以达到利用清洁燃料应对国际海事组织硫排放新规的目的。据悉,该集团已在1艘小型氢动力客船上完成了运营测试。该集团的航运业务由干散货运营商Bocimar、化学品运营商Bochem、油船运营商Botank与集装箱运营商Delphis构成,现有56艘散货船。
    • 卫汉青123
    • 摘要: 公元2018年5月,正是鲜花盛开、碧草连天的季节。凤凰岭下,稻香湖畔,风景优美的稻香湖景酒店,迎来了一场别具芳香的文化盛宴——2018(北京·海淀)比利时布鲁塞尔国际葡萄酒大奖赛。比利时布鲁塞尔国际葡萄酒大奖赛,简称CMB大奖赛,是世界上最具权威的三大国际葡萄酒大奖赛之一,也是世界上唯一在不同的国家和城市举办的葡萄酒大奖赛,素有酒界“奥斯卡”之称。
    • George Chapline; James Barbieri
    • 摘要: We introduce a novel model for the origin of the observable universe in which a flat universe with a positive vacuum energy is proceeded by a flat universe with a negative vacuum energy. A negative vacuum energy is consistent with a supersymmetric ground state similar to that predicted by superstring theories. A positive vacuum energy could emerge as a result of the gravitational collapse of the negative vacuum energy universe when the matter temperature reaches a characteristic value where supersymmetry is strongly broken. In principle this allows one to derive all the features of our expanding universe from a single parameter: the magnitude of the pre-big bang negative vacuum energy density. In this paper, a simple model for the big bang is introduced which allows us to use the present day entropy density, and temperature fluctuations of the CMB, together with the present day density of dark matter, to predict the magnitude of the negative vacuum energy. This model for the big bang also makes a dramatic prediction: dark matter consists of compact objects with masses on the order of 104 solar masses. Remarkably this is consistent with numerical simulations for how the primordial fluctuations in the density of dark matter give rise to the observed inhomogeneous distribution of matter in our universe. Our model for the big bang also allows for the production of some compact objects with masses greater than 104 solar masses which are consistent with observations of massive compact objects at the center of the earliest galaxies.
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