低压电力线远程载波集中抄表系统的应用

介绍了低压配电网载波抄表系统,阐述了载波系统组成部分和抄表流程,分析了载波系统的特点及其社会效益和经济效益。     

基于CCD摄像系统机械式精量排种器的动态特性分析

为建立精量排种器性能分析系统,本文运用高速摄像技术,通过对拍摄的动态图像的详细分析,提取运动种子的下落姿态和轨迹,确定了造成排种器漏播的部分因素以及合理的试验因素,得出其最优组合。实验结果表明：CCD摄像检测精度满足排种器使用的要求,因此,基于CCD摄像系统进行精量排种器性能研究是可行的,本研究具有实际的参考价值。     

电力计量系统分流窃电检测监控装置设计

提出一种新的应用于高压电力计量系统的电能表电流线圈被短接分流窃电的故障检测方法.首先通过电流互感器二次回路特性分析,得出电流互感器二次绕组端电压及其二次回路电流二者的比值与电能表电流线圈被短接故障存在密切的关系,其次,设计了基于单片机技术的分流窃电检测监控装置,试验验证了该分流窃电检测监控装置能准确地识别出电能表电流线圈被短接分流窃电的行为.     

A new species of Plagiodontes from Argentina,and new data on the anatomy of four other species in the genus (Gastropoda: Orthalicidae,Odontostominae)

Abstract

Plagiodontes weyrauchi sp. nov. is among the smallest species in the genus Plagiodontes (Doering, 1877). Statistical multivariate analyses confirmed its distinctiveness from other species, mostly because of its high number of whorls (8–9.75), relatively small width, and low proportions of last whorl and aperture length to shell length; multivariate discriminant analysis applied to this species and its most similar relative, P. multiplicatus parvus, correctly identified 100%?of specimens. Pallial and genital anatomy supports P. weyrauchi as a different species, mainly because of the position of the ureteric pore, the small general size of the genital system, the presence of an accessory lobe alongside the verge, and the vaginal internal structure. Internal anatomy of four other small-sized taxa in the genus was studied. Two of them have a verge with no accessory lobe [P. dentatus (Wood, 1828) and P. patagonicus (d'Orbigny, 1835)], while the remaining two have an accessory lobe with different characteristics [P. rocae Doering, 1881 and P. multiplicatus parvus (Hylton-Scott, 1952 Hylton-Scott, M I. 1952. Nuevos moluscos terrestres del norte argentino. Acta Zool Lilloana., 10: 5–29.  [Google Scholar])]. Internal structure of the vagina also shows specific differences among Plagiodontes species; their phylogenetic significance will be further investigated.     

Barrels and pagodas: clarifying the identity and variability of two nominal taxa of carinated land snails in the genus Plagiodontes (Gastropoda: Orthalicidae: Odontostominae)

Plagiodontes weyenberghii (Doering, 1877 Doering, A. 1877. [“1875”]. Apuntes sobre la fauna de moluscos de la República Argentina (continuación). Periód Zool, 2: 219–259.  [Google Scholar]) has a shell with a strong suprasutural keel; the species inhabits a restricted area in Central Argentina. Plagiodontes weyenberghii minor (Parodiz, 1939 Parodiz, JJ. 1939. Revisión de Plagiodontes y Scalarinella (Odontostominae). Physis, 17: 711–734.  [Google Scholar]) was described as a subspecies with obese shells and broader geographic distribution; some populations were sympatric with Plagiodontes daedaleus (Deshayes, 1851). A discriminant analysis on 244 adult shells combined with original information on the internal anatomy confirmed the distinctiveness of P. weyenberghii weyenberghii, whereas P. weyenberghii minor showed a broad overlap with P. daedaleus and no evidence of anatomical differences. As a consequence, P. weyenberghii minor is considered a junior subjective synonym of P. daedaleus daedaleus (Deshayes, 1851). Plagiodontes weyenberghii (Doering, 1877 Doering, A. 1877. [“1875”]. Apuntes sobre la fauna de moluscos de la República Argentina (continuación). Periód Zool, 2: 219–259.  [Google Scholar]) has unique characteristics such as the weak vascularization of the pallial system, the relative size of the penial papilla and its accessory lobe, the markedly swollen distal portion of the bursa copulatrix duct, the spermoviduct with two whorls, and the vagina with a medial depression.     

质量流量计在油田油井计量中的应用

介绍了科氏力质量流量计的组成;阐述了油井计量方案的选择,质量流量计在油井计量应用中的设计和选型;重点论述了质量流量计在苏丹大尼罗河石油公司油井计量中的应用,分析了出现的应用问题和相应的解决方法。     

三种水生植物营养器官的比较解剖学研究

通过对三种水生植物营养器官的解剖观察发现这几种植物根的本质部不发达,茎中有发达的通气组织或中空,叶片薄或线形,等面叶,叶表皮中含叶绿体,2个种栅栏组织退化,所有这些特征均与其水生环境中的水对植物体有支持力,水中缺少氧气,光照缺乏等因素有关。     

Venous branching asymmetry in the pygmy squid Idiosepius (Cephalopoda: Idiosepiida) with reference to its phylogenetic position and functional significance

The Japanese pygmy squid, Idiosepius paradoxus (Ortman, 1888), is one of the smallest cephalopods in the world. Their fully described developmental stages and the ready availability of eggs also make pygmy squids suitable material for cephalopod developmental studies. However, their phylogenetic position among the Decabrachia is unclear. We investigated the vascular anatomy of the Japanese pygmy squid using serial sections of the adult. Their venous system is different from that of teuthoids with respect to the presence of the vena cava sinistra. The branching pattern of the vena cava is similar to that of the sepiolids in having two pathways, but different in that it lacks a connection above the hind gut. The Idiosepius heart is also similar to that of sepiids in having the genital artery located dorsally. These features of Idiosepius agree with molecular phylogenies suggesting they are related to the sepiolids. We discuss the venous branching asymmetry with reference to its phylogenetic and functional significance.