“Alme ardeb” is a conventional beverage made from sugar and tamarind, season with other ingredients and highly prized by the population of the northern regions of Cameroon. Despite the importance of this traditional...“Alme ardeb” is a conventional beverage made from sugar and tamarind, season with other ingredients and highly prized by the population of the northern regions of Cameroon. Despite the importance of this traditional drink, the manufacturing process and quality attributes are still unknown. As such, a study was undertaken to describe the manufacturing process and characterise the quality of “Alme ardeb”. A survey was conducted in the Diamaré division of the Far north region. An ethnographical technique accompanied with semi-structured questionnaires and interviewing were used for collecting data needed to elaborate the production process. Forty-nine (49) samples of “Alme ardeb” were taken from 49 women producers in the different sites representing 10 samples per site and the sensory, physicochemical, phytochemical and microbiological properties were assessed according referenced techniques. The field survey reveals that the production of “Alme ardeb” is conventional and rudimentary involving two classical units of operation, caramelisation and boiling. The pH and titratable acidity of “Alme ardeb” were insignificant (p ≥ 0.05) except for the soluble solids, electrical conductivity and total sugar. The pH is acidic ranging between 4.06 ± 0.01 and 4.74 ± 0.05 with an oscillating titratable acidity ranging from 0.61% ± 0.022% to 0.65% ± 0.01% and an average soluble solids content of about 10.74 °Brix. Similarly, the total sugar content varies between 51.25 ± 0.18g·L<sup>-1</sup> and 61.37 ± 0.18 g·L<sup>-1</sup> with a conductivity that fluctuates around 351 μS·cm<sup>-1</sup> and 707 μS·cm<sup>-1</sup>. In addition, the average polyphenol, flavonoid and tannin contents were 2.2g EAG·L<sup>-1</sup>, 0.58 g·EQL<sup>-1</sup> and 0.36 g·ECL<sup>-1</sup> respectively, with a free radical scavenging capacity of 52.18%. The beverage revealed a complete absence of Salmonella with a doubtful hygienic quality. The total aerobic plate count varied from (4.1 ± 0.014) × 10<sup>4</sup> CFU·mL<sup>-1</sup> to (8.2 ± 0.007) × 10<sup>7</sup> CFU·mL<sup>-1</sup>, total coliforms from (4.3 ± 0.6) × 10<sup>2</sup> CFU·mL<sup>-1</sup> to (1.05 ± 0.7) × 10<sup>5</sup> CFU·mL<sup>-1</sup>, faecal coliforms from non-detected to (4.1 ± 0.07) × 10<sup>2</sup> CFU·mL<sup>-1</sup> and the fungal flora ranged from 0.0 to (6.5 ± 0.7) × 10<sup>3</sup> CFU·mL<sup>-1</sup>. However, the panelists judged the beverage as being acidic with a brownish colour and a sweet caramelized taste. Consequently, the beverage was highly palatable and consumed with an overall score that went from 13.48 ± 3.32 to 15.81 ± 4.47.展开更多
目的:比较分析PLo S ALMs与Altmetrics评分、单篇论文学术评价指标之间的相关性及对单篇论文的评价效度。方法:以PLo S系列期刊PLo S Biology、PLo S Medicine为例,基于PLo S ALMs论文层面计量指标数据,分析比较其阅览量、下载量、讨论...目的:比较分析PLo S ALMs与Altmetrics评分、单篇论文学术评价指标之间的相关性及对单篇论文的评价效度。方法:以PLo S系列期刊PLo S Biology、PLo S Medicine为例,基于PLo S ALMs论文层面计量指标数据,分析比较其阅览量、下载量、讨论量、保存量、被引频次、推荐量与Altmetrics评分、h指数、学术迹T之间的相关性以及对单篇论文的评价效果。结果:阅览量、下载量、讨论量与被引频次、h指数有正相关性,推荐量与h指数、学术迹无关。Altmetrics评分与阅览量、下载量和讨论量呈中度相关性,与被引频次呈弱相关。结论:PLo S ALMs是一个多维评价,应该应用多指标测度,才能体现研究成果的综合实力。展开更多
介绍了一个基于覆盖网(Overlay Network)技术的应用层组播视频直播系统,它在IPv6网络上实现,提出了用IP地址最大匹配法与时延来寻找最优父结点。系统采用代理的结构和三级的服务模型,此外本系统基于当前流行Windows Media Technology技...介绍了一个基于覆盖网(Overlay Network)技术的应用层组播视频直播系统,它在IPv6网络上实现,提出了用IP地址最大匹配法与时延来寻找最优父结点。系统采用代理的结构和三级的服务模型,此外本系统基于当前流行Windows Media Technology技术,对流媒体数据进行处理。展开更多
随着大型风电基地建设,上游风机在运行时会使下游风场风速下降,湍流度增大,造成下游风机发电功率降低,加剧风机的疲劳破坏并缩短其服役周期。因此,亟需开展风机尾流研究,明确其特性及演化规律。为了揭示不同入流及偏航角下的单风机尾流...随着大型风电基地建设,上游风机在运行时会使下游风场风速下降,湍流度增大,造成下游风机发电功率降低,加剧风机的疲劳破坏并缩短其服役周期。因此,亟需开展风机尾流研究,明确其特性及演化规律。为了揭示不同入流及偏航角下的单风机尾流特性,基于单风机尾流风洞试验,验证基于大涡模拟(Large Eddy Simulation,LES)结合致动线模型(Actuator Line Model,ALM)数值模拟方法的准确性;基于LES-ALM模拟方法研究入流风场(包括风速及湍流度)及偏航角对风机尾流特性的影响,阐明正负偏航角下单风机尾流的对称性。结果表明:随着背景湍流度的增大,风机尾流恢复速度加快;当入流条件相同时,风机设置正负对称偏航角,其尾流风速也表现出一定的对称性;风机偏航角越大,风机尾流膨胀宽度会逐渐减小,并降低尾流风速的亏损程度。展开更多
文摘“Alme ardeb” is a conventional beverage made from sugar and tamarind, season with other ingredients and highly prized by the population of the northern regions of Cameroon. Despite the importance of this traditional drink, the manufacturing process and quality attributes are still unknown. As such, a study was undertaken to describe the manufacturing process and characterise the quality of “Alme ardeb”. A survey was conducted in the Diamaré division of the Far north region. An ethnographical technique accompanied with semi-structured questionnaires and interviewing were used for collecting data needed to elaborate the production process. Forty-nine (49) samples of “Alme ardeb” were taken from 49 women producers in the different sites representing 10 samples per site and the sensory, physicochemical, phytochemical and microbiological properties were assessed according referenced techniques. The field survey reveals that the production of “Alme ardeb” is conventional and rudimentary involving two classical units of operation, caramelisation and boiling. The pH and titratable acidity of “Alme ardeb” were insignificant (p ≥ 0.05) except for the soluble solids, electrical conductivity and total sugar. The pH is acidic ranging between 4.06 ± 0.01 and 4.74 ± 0.05 with an oscillating titratable acidity ranging from 0.61% ± 0.022% to 0.65% ± 0.01% and an average soluble solids content of about 10.74 °Brix. Similarly, the total sugar content varies between 51.25 ± 0.18g·L<sup>-1</sup> and 61.37 ± 0.18 g·L<sup>-1</sup> with a conductivity that fluctuates around 351 μS·cm<sup>-1</sup> and 707 μS·cm<sup>-1</sup>. In addition, the average polyphenol, flavonoid and tannin contents were 2.2g EAG·L<sup>-1</sup>, 0.58 g·EQL<sup>-1</sup> and 0.36 g·ECL<sup>-1</sup> respectively, with a free radical scavenging capacity of 52.18%. The beverage revealed a complete absence of Salmonella with a doubtful hygienic quality. The total aerobic plate count varied from (4.1 ± 0.014) × 10<sup>4</sup> CFU·mL<sup>-1</sup> to (8.2 ± 0.007) × 10<sup>7</sup> CFU·mL<sup>-1</sup>, total coliforms from (4.3 ± 0.6) × 10<sup>2</sup> CFU·mL<sup>-1</sup> to (1.05 ± 0.7) × 10<sup>5</sup> CFU·mL<sup>-1</sup>, faecal coliforms from non-detected to (4.1 ± 0.07) × 10<sup>2</sup> CFU·mL<sup>-1</sup> and the fungal flora ranged from 0.0 to (6.5 ± 0.7) × 10<sup>3</sup> CFU·mL<sup>-1</sup>. However, the panelists judged the beverage as being acidic with a brownish colour and a sweet caramelized taste. Consequently, the beverage was highly palatable and consumed with an overall score that went from 13.48 ± 3.32 to 15.81 ± 4.47.
文摘目的:比较分析PLo S ALMs与Altmetrics评分、单篇论文学术评价指标之间的相关性及对单篇论文的评价效度。方法:以PLo S系列期刊PLo S Biology、PLo S Medicine为例,基于PLo S ALMs论文层面计量指标数据,分析比较其阅览量、下载量、讨论量、保存量、被引频次、推荐量与Altmetrics评分、h指数、学术迹T之间的相关性以及对单篇论文的评价效果。结果:阅览量、下载量、讨论量与被引频次、h指数有正相关性,推荐量与h指数、学术迹无关。Altmetrics评分与阅览量、下载量和讨论量呈中度相关性,与被引频次呈弱相关。结论:PLo S ALMs是一个多维评价,应该应用多指标测度,才能体现研究成果的综合实力。
文摘随着大型风电基地建设,上游风机在运行时会使下游风场风速下降,湍流度增大,造成下游风机发电功率降低,加剧风机的疲劳破坏并缩短其服役周期。因此,亟需开展风机尾流研究,明确其特性及演化规律。为了揭示不同入流及偏航角下的单风机尾流特性,基于单风机尾流风洞试验,验证基于大涡模拟(Large Eddy Simulation,LES)结合致动线模型(Actuator Line Model,ALM)数值模拟方法的准确性;基于LES-ALM模拟方法研究入流风场(包括风速及湍流度)及偏航角对风机尾流特性的影响,阐明正负偏航角下单风机尾流的对称性。结果表明:随着背景湍流度的增大,风机尾流恢复速度加快;当入流条件相同时,风机设置正负对称偏航角,其尾流风速也表现出一定的对称性;风机偏航角越大,风机尾流膨胀宽度会逐渐减小,并降低尾流风速的亏损程度。
