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现代传输 2023年第3期 45-49页

作者：王晨刘晓娟刘德强中国信息通信研究院北京100191 中国联合网络通信有限公司北京市分公司北京100052

本文介绍了ODN中阻燃产品和相关标准,对比了不同产品的阻燃要求和试验方法。分析了标准中存在的问题并提出了相关建议。详细介绍了针焰试验方法(GB/T 5169.5-2008)、本生灯型火焰试验方法(YD/T 694-2004)及1k W预混合型火焰试验方法(GB/... 详细信息

本文介绍了ODN中阻燃产品和相关标准,对比了不同产品的阻燃要求和试验方法。分析了标准中存在的问题并提出了相关建议。详细介绍了针焰试验方法(GB/T 5169.5-2008)、本生灯型火焰试验方法(YD/T 694-2004)及1k W预混合型火焰试验方法(GB/T 18380.12-2008)三种方法,分析了试验方法存在的问题并提出了改进建议。

关键词： ond 阻燃标准化试验方法

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Assessing the Variability of Heavy Rainfall during October to December Rainfall Season in Tanzania

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Atmospheric and Climate Sciences 2021年第2期11卷 267-283页

作者： Lovina Peter Japheth Guirong Tan Ladislaus Benedict Chang’a Agnes Lawrence Kijazi Kantamla Biseke Mafuru Isack Yonah Tanzania Meteorological Authority Dar es Salaam Tanzania Nanjing University of Science and Technology Nanjing China

Heavy rainfall is one of the primary causes of flood during rainy season in Tanzania leading to severe socio-economic impacts. The study aimed at assessing and characterizing the variability of Heavy Rainfall Events (HREs) using Empirical Orthogonal Function (EOF), Mann-Kendal (MK) trend test, Correlation and Composite analysis methods. Based on the daily-observed precipitation and reanalysis data sets for the October to December (ond) rainfall season of 35 years (1981-2015), the spatial and temporal characteristics of HREs in Tanzania are studied. The relationship between heavy rainfall (HR) and large-scale circulation anomalies including the Indian Ocean dipole (IOD) and El Ni?o southern oscillation (ENSO) indices was assessed. The study found that, approximately 590 HREs were concentrated over northern sector and coastal belt of Tanzania. The monthly variability indicates that HREs are more pronounced in December followed by November while October being the least affected. The occurrence of HREs over the Lake Victoria, Kigoma and Tabora is largely attributed to low-level convergence of westerlies and enhanced moisture from Congo basin accompanied by a pronounced rising limb of Indian Walker circulation cell. A time-series analysis of HRE exhibits an inter-annual variation characterized by a slightly increasing trend, though the computed trends were not statistically significant at 95% confidence level. In most part of Tanzania HREs were positively correlated with both ENSO and IOD indices, underscoring the critical role of ENSO and Indian Ocean dynamic in modulating rainfall variability over the region. In general, it has been found that most of the HREs are generally triggered or amplified by large-scale circulation patterns such as ENSO and IOD.

关键词： Rainfall Variability Heavy Rainfall Events ond Tanzania

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Assessment of the Evolution and Socio-Economic Impacts of Extreme Rainfall Events in October 2019 over the East Africa

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Atmospheric and Climate Sciences 2020年第3期10卷 319-338页

作者： Ladislaus Benedict Chang’a Agnes Lawrence Kijazi Kantamla Biseke Mafuru Alfred Lawrence Kondowe Sarah Emirald Osima Habiba Ismail Mtongori Hashim Karim Ng’ongolo Omari Hamisi Juma Edward Michael Tanzania Meteorological Authority Dar es Salaam Tanzania

This study aimed at establishing and quantifying the evolution and socio-economic impacts of extreme rainfall events in October 2019. The study also focused on ascertaining the extent to which the Indian Ocean Dipole (IOD) and the El Ni?o Southern Oscillation (ENSO) influenced anomalous rainfall over East Africa (EA) in October 2019. It employed Singular Value Decomposition (SVD) methods to analyze inter-annual variability of EA rainfall and the Sea Surface Temperature Anomalies (SSTA) over the Indian and Pacific Ocean with a focus on October to December 2019 rainfall season. The SVD analysis enabled the exploration of the leading modes from the mean monthly rainfall and SSTs leading to the determination of the likely influence of the IOD and ENSO respectively. The first SVD coupled modes, which dominate the co-variability between the October rainfall over the EA domain, and SSTA over the Indian and Pacific Oceans based on 1981 to 2010 climatology indicate the monopole positive co-variability with rainfall over the entire EA domain. The corresponding spatial pattern for the SSTA over the Indian Ocean (IO) recaptures the positive IOD event while the central equatorial Pacific Ocean (i.e., over Ni?o 3.4 region) reveals a monopole positive loading, a typical signal for the warm phase of ENSO. The positive rainfall anomaly over the EA during October is found to be associated with either the IOD event or ENSO condition events independently or in phase. However, the inter-annual variability between October rainfall over EA and ENSO reveals a moderate relationship (r = 0.4212) while a robust association (r = 0.7084) is revealed with IOD. Comparatively, the October 2019 rainfall anomaly peaks the highest in history over the EA and was found to be coupled with highest positive IOD event in record. Unlikely, the 1997 October rainfall (which peaked the second in history), was associated with the co-occurrence of the positive phase of ENSO and

关键词： Indian Ocean Dipole (IOD) ENSO Sea Surface Temperature Extreme Events ond

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An Assessment of the Seasonal Rainfall and Its Societal Implications in Zanzibar Islands during the Season of October to December, 2019

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Atmospheric and Climate Sciences 2020年第4期10卷 509-529页

作者： K. H. Kai A. L. Kijazi S. E. Osima Tanzania Meteorological Authority (TMA) Kisauni Zanzibar Tanzania TMA Ubungo Plaza Dar es Salaam Tanzania

The assessment of the performance of the October to December (ond), 2019 rainfall season in Zanzibar (Unguja and Pemba) with reference to local downscaled Tanzania Meteorological Authority (TMA) forecast, and regional (Intergovernmental Authority on Development Climate Prediction and Application Center (IGAD-ICPAC) weather forecasts were assessed by comparing the long term average of ond rainfall data and previous ond rainfall seasons of 2016, 2017 and 2018 as well as extreme positive Indian Ocean Dipole (IOD) during ond seasons of 1961, 1994, 1997, 2006 and 2019 for Zanzibar. The study assessed zonal (u) and meridional (v) winds at 850 and 200 mb, monthly and dekadal sea surface temperature (SST);the Madden Julien Oscillations (MJO) forecast reports and the ocean heat content data. Both gridded and observed datasets were processed into dekadal, monthly and seasonal averages and then analysed. The results revealed that, based on the observations, above normal rainfall of 936 and 908 mm were reported at stations of Kisauni (Unguja) and Karume airport (Pemba) during 2019 ond season. This amount was the first and second ever recorded for the extreme positive IOD during ond seasons of 1961, 1994, 1997, 2006 and 2019, and also the first for the previous higher ond rainfall seasons of 2016, 2017 and 2018 which was highly variable. Moreover, these values were second ever-recorded highest ond rainfall since 1916 to 2019 where the first one was observed in 1961. Furthermore, the results revealed that 2019 ond seasonal rainfall had the highest amount of contribution based on historical climatology. For instance, the 2019 ond rainfall for Kisauni, Pemba airport and Matangatuani contributed to 198%, 303% and 231% of the long term (1987-2016) mean ond rainfall in Zanzibar. Indeed, the results show that the presence of the MJO during ond and the enhanced positive IOD was among the causes for the observed wetness of the 2019 ond in Zanzibar and most parts of the country. Moreover, the dominant easterly, southeasterly and northw

关键词： ond Rainfall Forecast Performance Sea Surface Temperatures MJO and IOD

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奥丹西隆对小鼠吗啡条件性位置偏爱效应的影响

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中国药物依赖性杂志 2004年第2期13卷 105-108页

作者：徐美林余涓陈崇宏福建医科大学药理学教研室福州350004

目的 :探讨 5 -HT3 型受体特异性拮抗剂奥丹西隆对吗啡诱导的条件性位置偏爱 (CPP)效应的影响。方法 :建立小鼠吗啡CPP模型 ,观察奥丹西隆对CPP的影响。结果 :吗啡 (5mg·kg-1,sc)可诱导小鼠对伴药箱产生显著的CPP ;测试前 30min注射奥... 详细信息

目的 :探讨 5 -HT3 型受体特异性拮抗剂奥丹西隆对吗啡诱导的条件性位置偏爱 (CPP)效应的影响。方法 :建立小鼠吗啡CPP模型 ,观察奥丹西隆对CPP的影响。结果 :吗啡 (5mg·kg-1,sc)可诱导小鼠对伴药箱产生显著的CPP ;测试前 30min注射奥丹西隆 (0 0 1- 1mg·kg-1,sc)不影响小鼠已形成的对吗啡的位置偏爱 ;而训练阶段于每次注射吗啡同时注射奥丹西隆 (0 0 1- 0 1mg·kg-1,ip)可拮抗小鼠对吗啡的CPP效应 ,但较大剂量奥丹西隆 (1mg·kg-1,ip)则不影响其效应 ,而且此剂量单独给药亦表现出自身的CPP潜力。结论 :一定剂量的奥丹西隆可拮抗小鼠对吗啡的偏爱效应的获得 ,但不影响其表达 ,提示该类药物有治疗阿片类依赖的潜力。

关键词：奥丹西隆小鼠吗啡条件性位置偏爱效应 CPP ond 给药程序

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