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311.
Louise Bedsworth 《Climatic change》2012,111(1):101-118
California is home to some of the worst air quality in the nation and ninety percent of the state’s population lives in areas
that are out of attainment with at least one of the National Ambient Air Quality Standards. Increasing temperatures associated
with climate change will make meeting air quality standards more difficult. Under a changing climate, additional emission
reductions will be needed to achieve clean air standards. These additional emission reductions and associated costs are called
the “climate penalty.” Air quality planning is the process of assessing the emission reductions needed to meet air quality
standards and outlining the programs and policies that will be implemented to achieve these emission reductions. This paper
reviews the challenges that a changing climate will pose for air quality planning in California and identifies opportunities
for adaptation. While state air quality regulators in California are taking enormous strides to address global warming, less
work is happening at the regional, air district level. Air districts are the agencies responsible for developing air quality
improvement plans. An important first step for regional air quality regulators will be to quantify the climate penalty and
understand their region’s vulnerability to climate change. Limitations in regulatory authority could impede measures to improve
preparedness. Regional agencies will likely need to look to state and federal agencies for additional emission reductions. 相似文献
312.
Abigail M. Smith Catherine R. McGourty Louise Kregting Andrew Elliot 《新西兰海洋与淡水研究杂志》2013,47(6):1297-1304
Serpulid patch reefs of Galeolaria hystrix Mörch, 1863 were found in water depths of 9–16 m in Big Glory Bay, Paterson Inlet, Stewart Island, and here we report preliminary studies of these important habitat‐formers. This is the first observation of this species in subtidal patch reefs; 114 reefs were noted in a survey of 28 000 m2. Most reefs were 1–5 m in diameter, and up to 1.5 m high. Up to 65% of the serpulid tubes were occupied by living G. hystrix during a mid‐winter diving survey; 64% of reefs observed were whole, whereas 36% were broken or dead. Radiometric dating of a basal specimen of reef carbonate showed it to be less than 50 years old. Production of high‐Mg calcite, ranging from 9 to 11 wt% MgCO3, by G. hystrix may be as much as 11 kg CaCO3 m‐2y‐1, but was not reflected in surrounding sediments, which were dominantly terrigenous muds. A rich reef fauna, both sessile and motile, was associated with the reefs. Further study of these unusual temperate reefs is strongly recommended. 相似文献
313.
314.
Using a CCD as detector, we have observed three nebulosities not yet listed in catalogues; they all present a planetary nebula morphology and are situated in the immediate neighbourhood (less than 3 arc min to the East) of NGC 1714. Observations have been made through interference filters centered on the main emission lines of these objects.The observations were made at the E.S.O. in La Silla (Chile).European Southern Observatory, La Silla, Santrago de Chile. 相似文献
315.
Barbara Louise Endemao Walker 《The Professional geographer》2001,53(2):160-177
As processors and marketers of fish, women fishtraders in the Fanti town of Cape Coast, Ghana have become powerful financers and owners of canoes, nets, and other fishing equipment. Since the 1960s, when motors were first introduced to Ghana's artisanal canoe fleet, two interrelated processes have occurred in Cape Coast. First, Ghana's fisheries have become increasingly exploited and—in the case of some species—overfished. Second, the social relations of production in the artisanal sector have shifted from being socially embedded to being more market‐based and impersonal. I argue that two recent Women in Development (WID) projects in particular have contributed to the breakdown of fishtraders’ traditional economic networks and livelihood strategies: (a) loan schemes that target women's associations, and (b) the 1985 Intestate Succession Law, which reconfigured inheritance rights. These WID projects, based on western notions of gender and the household, have created disharmony and mistrust among Cape Coast's fishtraders rather than promoting their “development.” The breakdown of fishtraders’ labor and marketing organizations has resulted in increasingly desperate strategies to get fish, increased degradation of Ghana's marine environment, and uncertainty for the future of the coastal economy. 相似文献
316.
Macrofossil evidence indicates that the mid-Holocene hemlock [Tsuga canadensisL. (Carr.)] decline that occurred over a wide area in eastern North America was associated with phytophagous insect activity.In situhemlock macrofossils and insect remains found in a paludified dunefield at the northern limit of hemlock testify that two defoliation events occurred at 4910 ± 90 and 4200 ± 100 yr B.P., respectively. The sharp coincidence of remains from hemlock needles with chewing damage typical of hemlock looper feeding, head capsules from the hemlock looper (Lambdina fiscellaria) and the spruce budworm (Choristoneura fumiferana), absence of hemlock fruiting remains, and tree-ring anomalies in fossil hemlocks that died prematurely (<165 yr) suggest that defoliation affected hemlock reproductive capacity and pollen productivity, or more likely caused mass mortality. Our findings indicate that defoliation can affect ecosystems for centuries, especially when long-lived tree species are involved. 相似文献
317.
R. Louise 《Astrophysics and Space Science》1981,79(1):229-237
Monochromatic photographs in H, [Nii] 6584 and [Oiii] 5007 Å show many different details in the morphological structure of the Eskimo Nebula (NGC 2392). H and [Nii] images show, in a first approximation, similar structure (elliptical inner ring and broken outer ring) whereas both rings in [Oiii] are quite circular and regular in brightness. A photometric study using the method described by Louise (1974) gives various geometrical parameters of both rings which are practically the same for the observed lines. In other words, the classical stratification structure in planetary nebulae is not clearly observed in NGC 2392, in good agreement with previous observations (Wilson, 1950). This fact is probably a consequence of the peculiar structure in the geometry of the nebula. A model consisting of an inner toroid surrounded by a spherical shell is proposed to account for both photometric and spectroscopic observations. 相似文献
318.
R. Louise 《Earth, Moon, and Planets》1981,25(4):389-396
The well-known Titius-Bode law (T-B) giving distances of planets from the Sun was improved by Basano and Hughes (1979) who found: $$a_n = 0.285 \times 1.523^n ;$$ a n being the semi-major axis expressed in astronomical units, of then-th planet. The integern is equal to 1 for Mercury, 2 for Venus etc. The new law (B-H) is more natural than the (T-B) one, because the valuen=?∞ for Mercury is avoided. Furthermore, it accounts for distances of all planets, including Neptune and Pluto. It is striking to note that this law:
- does not depend on physical parameters of planets (mass, density, temperature, spin, number of satellites and their nature etc.).
- shows integers suggesting an unknown, obscure wave process in the formation of the solar system.
319.
Marielle Lacombe Vronique Garon Maurice Comtat Louise Oriol Joël Sudre Danile Thouron Nadine Le Bris Christine Provost 《Marine Chemistry》2007,106(3-4):489-497
Silicate has been determined in sea water by four different electrochemical methods based on the detection of the silicomolybdic complex formed in acidic media by the reaction between silicate and molybdenum salts. The first two methods are based on the addition of molybdate and protons in a seawater sample in an electrochemical cell. Cyclic voltammetry presents two reduction and two oxidation peaks giving four values of the concentration and therefore increasing the precision. Then chronoamperometry is performed on an electrode held at a constant potential. A semi-autonomous method has been developed based on the electrochemical anodic oxidation of molybdenum, the complexation of the oxidation product with silicate and the detection of the complex by cyclic voltammetry. This method is tested and compared with the classical colorimetric one during ANT XXIII/3 cruise across Drake Passage (January–February 2006). The detection limit is 1 μM and the deviation between both methods is less than 3% for concentrations higher than 10 μM. Finally a complete reagentless method with a precision of 2.6% is described based on the simultaneous formation of the molybdenum salt and protons in a divided electrochemical cell. This latter method should be very useful for developing a reagentless sensor suitable for long term in situ deployments on oceanic biogeochemical observatories. 相似文献
320.
The effects of light on the fluorescence characteristics and biochemical composition of a marine diatom Tha-lassiosira pseudonana in light and dark cycles were investigated with semi-continuous culture. The results indicate that, with the increase of growing light intensity, DCMU enhanced fluorescence yield (Fd/Chl), enhanced fluorescence ratio (Fd/F) , cellular carbohydrate content. carbohydrate/chlorophyll a and carbohydrate/protein ratio increased , but the fluorescence yield and cellular chlorophyll a content decreased; The protein content declined with the increase of light intensity in the range of 10- 100 μmol/ (m2·s) and increased at higher than 100 μmol/ (m2·s). Sampling time during the day had great effect on the relationships between growing light intensity and cellular chlorophyll a , carbohydrate content , carbohydrate/chlorophyll a and carbohydrate/protein ratio. 相似文献