UUV用锂二氧化锰电池

介绍了UUV用锂二氧化锰电池的工作原理,进行了放电性能试验及安全性试验。结果表明,锂二氧化锰电池具有高比能、长贮存寿命、免维护以及较好的安全性,是新一代UUV电源的理想选择。     

水下自航器用锂／二氧化锰电池组的散热处理

大型锂/二氧化锰电池组作为水下自航器的动力电源,以中高倍率电流工作时,会产生大量的废热,若不及时将废热传递至外界环境（海水）时,将对电池组的安全性产生恶劣影响。文中分析了锂/二氧化锰电池的热源和电池组的传热过程,并测量了电池的热功率,通过模拟电池组的废热功率探索了散热处理方法对电池组温度的影响。在水下自航器用锂/二氧化锰电池组设计时,采用综合散热处理方法能够合理控制电池组的温度,且有一定的温度冗余量。     

Saft公司获得美国国防后勤局多张锂离子电池订单

依照Saft公司与美国国防后勤局（DLA）签订的合同,Saft公司获得了总价为4．2百万美元的锂电池订单。Saft将提供其BA5590A／U锂二氧化硫（Li—SO2）电池,充电状态指示器及BA5372／U锂二氧化锰电池。这些电池用于军事便携设备中,如无线电通讯以及电子系统。     

锂-二氧化锰电池中关键材料的研究进展

锂-二氧化锰(Li/MnO2)一次电池在民用、军用领域都有着广泛的应用。它具有自放电率低、高比能、高功率、廉价、环保等特点。本文对锂-二氧化锰一次电池的嵌锂机制、正极材料、电解液、负极材料等关节环节的研究现状和发展进行了阐述,并对其不足与发展方向进行了分析。     

新型鱼雷推进电池的发展现状与展望

本文着重综述了国外新型鱼雷推进应用的铝／氧化银海水电池，锂／亚硫酰氯电池和热电池的研究情况，简述了有希望的锂／二氧化钴电池等的进步，并展望了它们的发展趋势。     

水下推进用高能电池

本文概要地介绍了几种可用于水下推进的高能电池,如海水电池,铅酸电池,燃料电池,热电池及锂系列电池的进展规模和应用前景,并认为水下推进用高能电池必奖在当今电动汽车用电池的大发展中得到进一步的提高。     

锂空（氧）气电池的研究概况及发展前景

本文概述了锂空（氧）气电池的研究进展,并对锂空（氧）气电池的未来发展前景作了展望。     

LiTFSI电解液应用于锂一次电池研究进展

锂一次电池具有高比能、高功率、低放电率等优点,为了提高锂一次电池组的安全性,必须摈弃传统的高氯酸锂电解液,采用已经商业化的LiTFSI电解液是最为快捷有效的解决途径.然而LiTFSI电解液应用于锂一次电池中面临腐蚀铝箔的关键问题,本文分析了LiTFSI电解液腐蚀铝箔的原因以及解决这一问题的途径.     

氢氟醚电解液在锂金属电池中的应用研究

无负极锂金属电池存在容量损失快和循环寿命短的缺点。本文设计制备一种氢氟醚电解液,探究其在无负极锂金属电池中的应用。采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)进行分析,结果表明该氢氟醚电解液对高面容量银碳基无负极锂金属电池的循环性能有着优良的改善作用。氢氟醚电解液减少了锂枝晶的产生,提高了沉积锂的致密性,在大于3 mAh/cm2的高面容量下,银碳基无负极锂金属电池在0.5C的倍率下50次循环后仍保持96.2%的平均库伦效率,展现了优良的循环性能和良好的倍率性能,1C倍率下容量保持率≥85%。     

美国船级社(ABS)发布《锂离子电池在船舶及海工行业应用指南(2022)》

2022年1月,美国船级社(ABS)发布了《锂离子电池在船舶及海工行业应用指南》(简称:《指南》),旨在为船东、运营商、船厂、设计公司和制造商制定安全标准。《指南》包含了目前行业中使用的锂离子电池类型,如锂钴氧化物、锂锰氧化物、锂镍锰钴氧化物、锂镍钴铝氧化物、锂磷酸铁和锂钛酸盐等。对于常规电池类型适用的要求,请参考ABS《海船规范》第4部分。对于水下潜航器电池适用的要求,请参考ABS《水下潜航器、系统及高压氧设施规范》第10部分和第11部分。     

Impact of regulation on the performances of long-distance transport services: A comparison of the different approaches in Sweden and Norway

Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.     

丁坝群坝田与主流水沙交换与冲淤机理综述

丁坝群不同平面布置方案下坝田与主流间的泥沙交换和地形变化是长江口深水航道回淤机理及减淤措施研究的重要内容,但以往研究不多。坝田与主流的泥沙交换及地形变化与紊流结构及时均流场有关,即与坝田-主流主界面混合层的大尺度相干结构和坝田内时均大尺度环流有关。在出水丁坝和淹没丁坝情况下坝田与主流的质量交换系数变化不大,约为0. 02左右。坝田不存在悬沙的平衡剖面(Rouse分布),悬沙和底沙均存在指向坝田的净输沙。坝田淤积达到准平衡状态需要5～6 a,但基本上在前2 a就达到了平衡。     

Evolving the subspace of the three-dimensional multiscale ocean variability: Massachusetts Bay

A data and dynamics driven approach to estimate, decompose, organize and analyze the evolving three-dimensional variability of ocean fields is outlined. Variability refers here to the statistics of the differences between ocean states and a reference state. In general, these statistics evolve in time and space. For a first endeavor, the variability subspace defined by the dominant eigendecomposition of a normalized form of the variability covariance is evolved. A multiscale methodology for its initialization and forecast is outlined. It combines data and primitive equation dynamics within a Monte-Carlo approach.The methodology is applied to part of a multidisciplinary experiment that occurred in Massachusetts Bay in late summer and early fall of 1998. For a 4-day time period, the three-dimensional and multivariate properties of the variability standard deviations and dominant eigenvectors are studied. Two variability patterns are discussed in detail. One relates to a displacement of the Gulf of Maine coastal current offshore from Cape Ann, with the creation of adjacent mesoscale recirculation cells. The other relates to a Bay-wide coastal upwelling mode from Barnstable Harbor to Gloucester in response to strong southerly winds. Snapshots and tendencies of physical fields and trajectories of simulated Lagrangian drifters are employed to diagnose and illustrate the use of the dominant variability covariance. The variability subspace is shown to guide the dynamical analysis of the physical fields. For the stratified conditions, it is found that strong wind events can alter the structures of the buoyancy flow and that circulation features are more variable than previously described, on multiple scales. In several locations, the factors estimated to be important include some or all of the atmospheric and surface pressure forcings, and associated Ekman transports and downwelling/upwelling processes, the Coriolis force, the pressure force, inertia and mixing.     

Analytical and experimental study of free vibration of beams carrying multiple masses and springs

The structures in engineering can be simplified intoelastic beams with concentrated masses and elastic spring supports.Studying the law of vibration of the beams can be a help in guidingits design and avoiding resonance. Based on the Laplace transformmethod, the mode shape functions and the frequency equations ofthe beams in the typical boundary conditions are derived. Acantilever beam with a lumped mass and a spring is selected toobtain its natural frequencies and mode shape functions. Anexperiment was conducted in order to get the modal parameters ofthe beam based on the NExT-ERA method. By comparing theanalytical and experimental results, the effects of the locations ofthe mass and spring on the modal parameter are discussed. Thevariation of the natural frequencies was obtained with the changingstiffness coefficient and mass coefficient, respectively. The findingsprovide a reference for the vibration analysis methods and thelumped parameters layout design of elastic beams used inengineering.     

Formation of Denmark Strait overflow water and its hydro-chemical composition

The dense overflow across the Denmark Strait is investigated with hydrographic and hydro-chemical data and the water mass composition of the Denmark Strait Overflow Water (DSOW) is determined by multivariate analysis. Hydrographical properties, the transient tracers CFC-11 and CFC-12, oxygen and nutrients are utilized for the water mass definitions. Distribution and characteristics of water masses north of Denmark Strait are described, the important water masses at the sill and the variability on weekly time-scales are discussed, and the entrainment and mixing of water into the overflow plume in the northern Irminger Basin is calculated. The analysis indicates that water masses both from the Nordic Seas and the Arctic Ocean are important for the formation of DSOW. It is found that water masses transported with the East Greenland Current make up about 75% of the overflow at the sill. The overflow at, and shortly south of, the sill is inhomogeneous with a low-salinity component dominated by Polar Intermediate Water. The high-salinity component of the overflow is mainly of Arctic origin. The water mass composition, and the short-term variability for 7 repeats of sections close to the sill are described, and these illustrate that the overflow is in fact a composite of a number of water masses with different formation and transport histories. This indicate that the overflow is a robust feature, but that it responds to variations in the circulation or atmospheric forcing that influences the formation of intermediate and deep water masses within the Arctic Mediterranean and the North Atlantic. At a section about 400 km south of the sill the overflow is well mixed and modified by entrainment of, mainly, Iceland–Scotland Overflow Water and Labrador Sea Water, together constituting 30% of the overflow plume. The entrainment of Middle Irminger Water dominates shortly downstream of the sill, before the overflow plume reaches too deep but the entrainment seems to be intermittent in time.     

钢-混凝土箱型组合斜拉桥主梁混凝土收缩徐变分析

组合梁斜拉桥兼有混凝土和钢结构的优点,但作为两种材料的结合体,混凝土收缩徐变会引起组合截面的应力重分配,可能促使混凝土裂缝的提前出现或加速裂缝的扩展,从而降低结构的受力性能和耐久性。采用有限元方法分析了混凝土收缩徐变对组合梁斜拉桥主梁应力重分布的影响,并对混凝土的加载龄期的影响进行了参数分析。计算结果表明：混凝土加载龄期越早,组合截面的应力重分布越明显;混凝土收缩徐变对混凝土桥面板的应力影响不大,但对钢梁应力影响较为显著,钢梁的应力增量达到钢材容许应力的30%左右。     

船舶制造技术成熟度评估系统

在船舶制造中,技术成熟度的评估意识薄弱且缺少信息化手段。通过确定评估指标、设定权重,建立船舶制造技术成熟度评估系统,由系统计算成熟度的得分和等级,从总体设计、建造工艺、船厂建造资源能力、船舶研制定型后等方面进行评估。该系统可减少返工带来的时间成本、人力成本,提高船舶制造技术成熟度评估的科学性、准确性、可靠性、灵活性及效率。     

Alterations in nutrient limitations — Scenarios of a changing Baltic Sea

Previous trend studies have shown increasing nitrogen and phosphorus as well as decreasing silica concentrations in the water mass of the Baltic Sea. This has had an impact on the amount of primary production, but also on the quality and succession of plankton species. Present study examines the spatial and temporal patterns of potential nutrient limitations in the Baltic Sea for the time period 1970–2000. Generally, low concentrations of DSi can limit the diatom blooms and such conditions are found in the Gulf of Riga and Gulf of Finland during spring and summer. Nutrient ratios, DSi:DIN, DSi:DIP and DIN:DIP, are often used to determine which nutrient may limit the primary production. Annual long-term temporal trends of silica to inorganic nitrogen and phosphorus respectively show consistent decreasing patterns. The largest slopes are detected during spring and summer for DSi:DIN and during spring for DSi:DIP ratios. For the DIN:DIP ratio significant slopes are only found in a few locations despite increasing levels for both nutrients, displaying a large variation in trends. In the open Baltic Proper the present trends are positive during winter and negative during spring and autumn. Gulf of Finland and Gulf of Riga are areas where both DSi:DIP and DSi:DIN ratios are found close to the Redfield ratios for diatoms. Together with the evaluated trends these suggest that the Gulfs may become silica limited in a relatively near future. These findings give some implications on the development and impact of changing nutrient concentrations.     

船用五螺杆泵低噪声工艺技术

本文通过对现有的某船用五螺杆泵的频谱特征和振动特性进行分析,找出主要振动噪声源,通过改进进口流道面积,并对现有的螺杆加工工艺进行研究和优化改进,改进后的设计通过样机的制造,并经过试验对比分析,进一步验证方法的可行性和预期减振效果。     

船闸自动控制系统的养护与检修

以连云港市盐灌船闸为例,对船闸自动控制系统应用一年来PLC的运行环境、日常维护、故障检修等进行总结,对水位计、限位开关等主要电气元器件的养护与优化进行分析,并对船闸液压、机械设备日常维护和常见故障处理进行探讨.总结了船闸自动控制系统的养护与检修方法.