排序方式: 共有23条查询结果,搜索用时 62 毫秒
11.
Transport and transformation of sulfur compounds over East Asia during the TRACE-P and ACE-Asia campaigns 总被引:4,自引:0,他引:4
Meigen Zhang Itsushi Uno Yasuhiro Yoshida Yongfu Xu Zifa Wang Hajime Akimoto Timothy Bates Trish Quinn Alan Bandy Byron Blomquist 《Atmospheric environment (Oxford, England : 1994)》2004,38(40):6947
On the basis of the recently estimated emission inventory for East Asia with a resolution of 1×1°, the transport and chemical transformation of sulfur compounds over East Asia during the period of 22 February through 4 May 2001 was investigated by using the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system with meteorological fields calculated by the regional atmospheric modeling system (RAMS). For evaluating the model performance simulated concentrations of sulfur dioxide (SO2) and aerosol sulfate (SO42−) were compared with the observations on the ground level at four remote sites in Japan and on board aircraft and vessel during the transport and chemical evolution over the Pacific and Asian Pacific regional aerosol characterization experiment field campaigns, and it was found that the model reproduces many of the important features in the observations, including horizontal and vertical gradients. The SO2 and SO42− concentrations show pronounced variations in time and space, with SO2 and SO42− behaving differently due to the interplay of chemical conversion, removal and transport processes. Analysis of model results shows that emission was the dominant term in regulating the SO2 spatial distribution, while conversion of SO2 to SO42− in the gas phase and the aqueous phase and wet removal were the primary factors that controlled SO42− amounts. The gas phase and the aqueous phase have the same importance in oxidizing SO2, and about 42% sulfur compounds (25% in SO2) emitted in the model domain was transported out, while about 57% (35% by wet removal processes) was deposited in the domain during the study period. 相似文献
12.
Gregory E. Blomquist 《Behavioral ecology and sociobiology》2009,63(9):1345-1352
Females of many cercopithecine primates live in stable dominance hierarchies that create long-term asymmetries among sets
of female relatives (matrilines) in access to limiting resources and shelter from psychosocial stress. Rank-related differences
in fitness components are widely documented, but their causes are unclear. Predicted breeding values from an animal model
for female age of first reproduction are used to discriminate between shared additive genetic and shared environmental effects
among the members of matrilines in a population of free-ranging rhesus macaques (Macaca mulatta). While age of first reproduction has a modest heritability (≈0.2), breeding values are distributed in a largely random fashion
among matrilines and contribute little to the observed rank-related differences in average age of first reproduction. These
results support the long-held, but previously unverified, contention that rank-related life history differences in female
cercopithecine primates are the result of environmental rather than genetic differences among them. 相似文献
13.
Ecolabeled paper towels are manufactured using post-consumer recycled material and sold in markets using a recycle logo. Environmentally conscious consumers purchase these paper towels and thereby contribute to improving environmental quality. In this paper, we estimate the implicit value placed by consumers on ecolabeled paper towels using a hedonic price function and conduct an expenditure analysis using Heckman's selection model. Using the data set from the Internet-based grocery stores called as Peapod we find that some consumers recognize ecolabels on paper towels and place a substantial, positive price premium on them. The expenditure analysis indicates that for the preferred functional form, the demand for ecolabeled paper towels is inelastic for environmentally conscious consumers. The simulated results from the selection model indicate that a small subsidy for ecolabeled paper towels will not substantially change consumers' purchase decisions. 相似文献
14.
Monoterpenes are structurally diverse natural compounds that play an essential role in the chemical ecology of a wide array
of organisms. A key enzyme in monoterpene biosynthesis is geranyl diphosphate synthase (GPPS). GPPS is an isoprenyl diphosphate
synthase that catalyzes a single electrophilic condensation reaction between dimethylallyl diphosphate (C5) and isopentenyl diphosphate (C5) to produce geranyl diphosphate (GDP; C10). GDP is the universal precursor to all monoterpenes. Subsequently, monoterpene synthases are responsible for the transformation
of GDP to a variety of acyclic, monocyclic, and bicyclic monoterpene products. In pheromone-producing male Ips pini bark beetles (Coleoptera: Scolytidae), the acyclic monoterpene myrcene is required for the production of the major aggregation
pheromone component, ipsdienol. Here, we report monoterpene synthase activity associated with GPPS of I. pini. Enzyme assays were performed on recombinant GPPS to determine the presence of monoterpene synthase activity, and the reaction
products were analyzed by coupled gas chromatography–mass spectrometry. The functionally expressed recombinant enzyme produced
both GDP and myrcene, making GPPS of I. pini a bifunctional enzyme. This unique insect isoprenyl diphosphate synthase possesses the functional plasticity that is characteristic
of terpene biosynthetic enzymes of plants, contributing toward the current understanding of product specificity of the isoprenoid
pathway. 相似文献
15.
16.
E. T. Blomquist M.D. 《Journal of the Air & Waste Management Association (1995)》2013,63(10):530-531
The author will describe the program of the Division of Air Pollution for developing air quality criteria and the present state of preparation of documents covering criteria for two broad classes of contaminants—the oxides of sulfur and photochemical oxidants. The preparation and content of these documents are briefly reported. 相似文献
17.
William Blomquist Tanya Heikkila Edella Schlager 《Journal of the American Water Resources Association》2004,40(4):925-936
ABSTRACT: This paper pursues more specifically the recommendations of a recent National Research Council report recommending greater attention to research on institutions in the field of water resource management. The important challenge for the future in institutional research lies in going beyond the observation that institutions are important and in explaining instead how institutions actually affect management options and outcomes. It is possible to illuminate the relationships between institutional features and water management through comparative institutional research. This paper offers recommendations for studying water institutions in a comparative context, including methodological recommendations concerning approaches to comparative institutional research, and topics for comparative institutional research that appear especially fruitful at this time. The example of conjunctive management is used to illustrate the importance of institutional factors in water management, drawing to some extent on the authors’ recent experience with a comparative study of conjunctive management institutions. 相似文献
18.
E.A. Andreeva N.K. Belisheva I.I. Freedlanskaya G.P. Pinaev G Blomquist 《Chemosphere》1982,11(4):377-381
Discrimination between malignant cells and their normal counterparts by surface properties has been demonstrated by means of two-phase aqueous polymer systems. Primary cultures of normal rat fibroblasts were treated with carcinogens DMBA and DEN. Nonmaliguant mouse fibroblasts of permanent line were treated with carcinogen DB(a,h)A. These treatments change their partition in the direction of their malignant counterparts. Noncarcinogenic phenanthrene affected the cell partition in the reverse direction. The possibility of using two-phase aqueous polymer systems for testing carcinogenic chemicals is discussed. 相似文献
19.
20.