Circuit prevents overcharging of secondary cell batteries

Circuit prevents battery cell overcharging by detecting and reducing the charging voltage to the open-circuit voltage of the battery when this current falls to a predetermined value. The voltage control depends on the fact that the charging current falls significantly when the battery nears its fully charged state

Method and apparatus for battery charge control Patent

Battery charging system with cell to cell voltage balanc

Social mobility, marriage and kinship among some gentry and yeoman families of Wantage Hundred, c. 1520 - c. 1670

The core of this thesis is the study of 12 gentry and yeoman families resident in Wantage Hundred between 1522 and 1670. Particular attention will be paid to the 4 main strategies of land acquisition, marriage, office-holding and education that could be adopted by each family group for advancement. In conjunction with this the pattern of social mobility within the families will be examined to determine what if any influence such strategies had on social status. The desire for any social elevation will be analysed to examine the notion that all yeoman were actively striving towards a gentry status, and that the gentry themselves were looking towards an aristocratic title. The actual title of `gentleman' and `yeoman' will be examined and their usage in this area analysed, and in particular the way the titles became accepted for merchants and tradesmen. The terms `open' and `closed' originally used to define nineteenth century parishes have been applied to Tudor and Stuart England. This hypothesis has been used to suggest that a resident gentry family could regulate the inflow of new families and could effectively `close' the parish to outside influences and stifle any upward social movement by the local yeoman families. In a parish without a resident gentry family it has been suggested that the opposite is true. New families could freely enter the community, and, more importantly, a yeoman family could control the parish, and, through recognition of local influence gain in social status. This hypothesis and its applicability to Wantage Hundred, will be examined and an assessment made as to whether it had any discernible effect on patterns of social mobility in the area. It can be deduced that throughout the period acquisition and ownership of land through purchase or marriage remained the paramount means of social advancement. Even so all the families used all the suggested strategies of advancement at some time during the period. However, it is apparent that not all families were actively striving for social advancement, particularly as differentiation between yeoman, merchant and gentleman became more blurred in the seventeenth century. In general it appears that yeoman families had greater opportunities for advancement and office-holding in open parishes

Electrochemical sintering process for producing electrodes from cadmium felt and a nickel or silver grid

Electrochemical sintering process produces cadmium felt electrodes. Two pieces of cadmium felt are sandwiched around a nickel screen or silver expanded metal grid, held together by mold compression, and electrochemically sinitered by being put through several charge and discharge cycles at low current density

Evaluation of the local employment impacts of enterprise zones: A critique

Enterprise zone policy is a potential tool for the regeneration of distressed areas, based primarily on tax incentives to businesses locating in the target areas. The tool has been tested in several countries over more than 35 years but there is no consensus on whether or not it is effective and efficient in creating jobs and reducing unemployment in targeted localities. This paper reviews seminal enterprise zone evaluations in the UK, USA and France. More than one-half of the studies reported local employment benefits but the others reported none and information is limited on what affects policy success. The paper argues that typically narrow-focus research designs and a-theoretical evaluation have contributed to the lack of consensus and policy insight, potentially exacerbated by non-exact data. It proposes richer evaluations with explicit theoretical frameworks, such as the one presented in the paper, more comparative work and the use of more accurate data

Imaging Polarimetric Observations of a New Circumstellar Disk System

Few circumstellar disks have been directly observed. Here we use sensitive differential polarimetric techniques to overcome atmospheric speckle noise in order to image the circumstellar material around HD 169142. The detected envelope or disk is considerably smaller than expectations based on the measured strength of the far-IR excess from this system

The Predatory Bird Monitoring Scheme (PBMS) Report 2006-7

The Predatory Bird Monitoring Scheme (PBMS) examines the levels of certain pollutants in selected wildlife species in Britain. It started in the 1960s to assess the impact of organochlorine pesticides on raptor populations, and the scheme is now the longest-running of its kind in the world. The aims of the PBMS are to monitor the levels of contaminants to determine how and why they vary between species and regions, how they are changing over time, and the risks they may have on individual birds and on their populations. Dead predatory birds are submitted to the PBMS by the public and by wildlife hospitals, veterinarian and zoological organisations. Eggs are collected, under licence, from a range of nests. The majority of these eggs are addled or deserted, although for some species, e.g. northern gannets, fresh egg are sampled. Second generation anticoagulant rodenticides (SGARs) are potentially toxic to all mammals and birds, and predators that feed upon rodents are particularly likely to be exposed to these compounds. Since 1983 the PBMS has monitored SGAR residues in barn owls, while kestrels have been monitored since 2001. The proportion of barn owls which have one or more SGARs in their liver increased from less than 10% in the 1980s to approximately 40% in the early 2000s. However, there has been a small decrease in this percentage in the last few years. A higher proportion of kestrels have detectable residues of SGARs in their liver than barn owls with 60% of birds received in the years 2001 to 2006 having one or more SGAR in their liver. There is no evidence of a change over time in the proportion ok kestrels with detectable liver SGAR residues. Overall, the high incidence of exposure amongst monitored species remains of concern. Sparrowhawk livers are analysed for a range of persistent organic pollutants (POPs) and heavy metals. Sparrowhawks are studied because they have a wide distribution across the Britain and can be used as a sentinel species for the terrestrial environment. Following restrictions on its use as an agricultural pesticide, mercury concentrations have declined in sparrowhawks. However, despite PCBs being banned in 1981, there has not been any long-term change in polychlorinated biphenyl (PCB) liver concentrations in sparrowhawks during the period 1968-2006. In herons, used as a sentinel species for freshwater habitats, both PCB and mercury concentrations have declined. In 2006, mean PCB and mercury concentrations in both species were below those thought to have an adverse effect on individual birds. Pollutants, such as mercury and PCBs, can affect development and hatchability.. Therefore, the PBMS monitors the levels of contaminants in the eggs of a range of species including those of conservation concern such as golden eagle and the re-introduced white-tailed sea eagle. Other species that are monitored are the northern gannet, which are used as a monitor of the marine environment, and merlin that hunt in upland habitats. In general, and specifically in 2006, the residues measured in the eggs of golden eagle and gannets are below those thought to have an adverse effect on bird eggs, but some residues in individual merlin eggs were at concentrations associated with effects in other species. Few white-tailed see eagle eggs are received for analysis by the PBMS but a large proportion of those eggs that have been analysed, including the egg collected in 2006, have DDE, PCB and mercury concentrations above levels associated with adverse effects on bird embryos and the hatching success of eggs. Despite the withdrawal of PCBs from manufacturing over 20 years ago, the evidence for declining PCB concentrations in predatory birds is equivocal, with declines in liver or egg residues in some species but not in others. Mercury concentrations in most species have not significantly changed during the monitoring period

Depletion of carriers and negative differential conductivity in an intrinsic graphene under a dc electric field

The heating of carriers in an intrinsic graphene under an abrupt switching off a dc electric field is examined taking into account both the energy relaxation via acoustic and optic phonons and the interband generation-recombination processes. The later are caused by the interband transitions due to optical phonon modes and thermal radiation. Description of the temporal and steady-state responses, including the nonequilibrium concentration and energy as well as the current-voltage characteristics, is performed. At room temperature, a nearly-linear current-voltage characteristic and a slowly-varied concentration take place for fields up to -- 20 kV/cm. Since a predominant recombination of high-energy carriers due to optical phonon emission at low temperatures, a depletion of concentration takes place below -- 250 K. For lower temperatures the current tends to be saturated and a negative differential conductivity appears below -- 170 K in the region of fields -- 10 V/cm.Comment: 8 pages, 10 figures, extended versio