二层交换机Hybrid端口模式的应用

本文通过对二层交换机各种端口模式的介绍，以实例讨论了利用其中Hybrid（混合）模式实现各端口之间隔离与互访的功能。     

Container river services and gateway ports: Similarities between the Yangtze River and the Rhine River

Abstract: Container ports located in a delta of navigable waterways generally strive to develop the inland river services as a competitive transport mode, with a view to serving local and distant hinterland regions. The spatial and functional development of river‐based container networks is location‐specific and time‐specific. While each barging network and associated seaport system has its own dynamics, similarities in development patterns cannot be excluded. This paper discusses similarities and dissimilarities between the spatial and the functional development of the container river service networks of the Yangtze River and the Rhine River. It is shown that the Yangtze service network has the tendency to converge, in more than one aspect, with the (historical) development pattern of inland container services in the Rhine basin.     

Micropropagation of red sanders (Pterocarpus santalinus L.) using mature nodal explants

In vitro clonal multiplication of Pterocarpus santalinus L. was achieved using mature nodal explants of a 10-year-old elite quality tree. Combinations of serial transfer technique and incorporation of antioxidants (250 mg/l L-ascorbic acid and 50 mg/l citric acid) into the culture medium helped to minimize medium browning and improve explant survival during shoot sprouting. About 70% of explants were sprouted on Murashige and Skoog (MS) liquid medium containing 4.4 μM 6-benzyladenine (BA). The explant harvest period also influenced the bud break and shoot sprouting in nodal explants. The combination of 4.4 μM BA and 2.2 μM thidiazuron (TDZ) was found to be the most suitable growth regulator for obtaining the highest percentage of nodal segment sprouting (74%–75%), the number of secondary shoots per primary shoot (two or three), the shoot length (5–6 cm), the number of new nodal segments generated per active explant (four or five), and the multiplication coefficient (3.5) within 6 weeks. Repeated subculturing of nodal explants obtained from shoot cultures enabled continuous production of healthy axillary shoots. At the end of the sixth passage, about 90% of nodal explants produced five or six healthy green shoots, each being about 6.6 cm long with six or seven nodes. Multiplication coefficient was also increased from the first subculture (5.4) to the sixth subculture (8.3). The best rooting response was achieved on solidified half-strength MS medium supplemented with 4.9 μM indole-3-butyric acid (IBA). About 70% of the micropropagated plantlets were established successfully in 20-cm pots containing a mixture of soil and farmyard manure (4 : 1 ratio) and formed new leaflets.     

广西防城港首次截获苜蓿黄萎病菌

从一批进境的美国苜蓿草样品中保湿分离得到了3株与苜蓿黄萎病菌(Verticillium albo-atrum)相似的目标菌VA1、VA2、VA3.该目标菌在PDA上生长迅速,菌丝生长0.8～1.0 mm/d,2～3 d即可生成肉眼可见的菌落斑点;菌落为白色圆形,边缘规则呈圆形,菌丝较致密,气生菌丝较少,菌落中心乳白色奶冻状;培养4～5 d即后产生气生典型轮枝状分生孢子梗,7～8 d后菌落中央表面因产生休眠菌丝开始变成黑褐色至黑色,20 d后菌落的表面和背面大部分均变黑色,仍不产生微菌核和厚垣孢子.该目标菌的纯培养用V.albo-atrum特异引物Vaa1/Vaa2进行检测,PCR 扩增后得到预期330 bp的产物片段,产物序列与V.albo-atrum相应序列的相似性为100％.从而鉴定确认该目标菌为苜蓿黄萎病菌V.albo-atrum.     

Serial invasive signal amplification reaction for genotyping permethrin-resistant (kdr-like) human head lice, Pediculus capitis

Permethrin resistance in the human head louse, Pediculus capitis De Geer (Anopulura: Pediculidae), has been reported worldwide, is associated with the knockdown phenotype, and elicits cross-resistance to DDT and the pyrethrins. Two point mutations, T929I and L932F, in the voltage-sensitive sodium channel α-subunit gene are responsible for permethrin resistance as a resistant haplotype (kdr-like). We have optimized a serial invasive signal amplification reaction (SISAR) protocol for the detection of these mutations using PCR amplified DNA fragments. SISAR distinguished all genotypes with high accuracy in a head louse population from Texas that was heterogeneous in terms of permethrin sensitivity. Using SISAR, resistance-conferring mutations are detected in a high throughput format, facilitating the efficient monitoring of permethrin resistance allele frequency in field populations.     

密集烟草烤窑智能化控制系统关键技术的研究

着重研究了自动控制多个烤窑温湿度的新方法,对同时监测和控制多个烤窑烘烤过程进行了优化设计。主要工作是在VC++的环境下串口通讯的编程和ARM控制芯片的C语言编程以及对控制系统外围硬件电路的设计。实验表明,采用这个设计方案不仅提高了烟草烘烤的质量,也节省了大量的劳动力。     

船舶压载水港口接收处理设施应用研究

船舶压载水公约已于2017年9月8日生效实施,规定了船舶压载水排放标准。目前,船舶需要通过安装压载水处理设备的方式满足公约的排放要求。但是,船用压载水处理设备性能的不稳定性及港口国监督检查的严苛,成为现阶段制约船舶有效履行公约的最大障碍。试从航运业的实际操作出发,结合压载水公约应急措施导则的要求,探讨使用压载水港口接收处理设施作为补充,来提升船舶履行公约能力的可行性。通过对压载水港口接收处理设施技术的必要性和可行性分析,对该技术与传统压载水处理技术进行了详细比较,并对其优势及应用前景进行了客观地探索和分析。可以预见,压载水港口接收处理设施作为一种新型的船舶压载水处理技术和港口应急技术,有着更为绿色、经济和高效的特点,在为船舶提供新的选择方案的同时,也为进一步保护海洋生态环境提供了有力的保障,体现了社会、经济及生态效益的高效统一。     

欧盟进境指定口岸管理概况及对我国的启示

对进口高风险农产品实施指定口岸制度是国际通行做法,近年来,国家质检总局先后对进境水果、种苗、粮食等高风险农产品采取指定口岸管理措施。本文搜集整理了欧盟针对非动物源性食品和饲料采取指定口岸管理措施的立法与实践情况,旨在从中找出值得我国学习和借鉴的地方,并结合我国指定口岸建设现状,就进一步做好指定口岸工作提出了相关建议。     

分布式智能控制系统在蔬菜大棚灌溉中的应用

该系统主要采用Atmel公司的ATmega16单片机作为微控器,利用温度传感器、湿度传感器、墒情检测传感器对大棚内温度、湿度及土壤墒情状况进行检测,然后将数据上传到服务器上进行分析,当需要进行灌溉时,服务器发送控制命令控制继电器的开关与闭合,完成灌溉任务.该系统采用串口转以太网通信方式,可以在任何有网络的条件下进行灌溉.     

巴黎备忘录全新NIR选船体系评估

从港口国监督（PSC）角度讨论了巴黎备忘录全新的NIR选船体系。选船是港口国监督极为重要的环节,合理的机制能极大提高船舶安全检查的效率。借助具体算例,对新旧选船方法展开差异性分析。同时剖析NIR背后隐藏的欧盟单边主义,深入发掘值得借鉴与警惕的问题。最后从法规及技术等层面,提出未来我国港口国监督选船机制的发展建议。