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901.
The importance of ammonia (NH3) in the atmosphere andits role in acidification is increasingly recognized. Adetailed emission inventory of NH3 for South Korea iscarried out for different sources using emission factors.Results indicate that the emission of ammonia has increasedby 21% over the last 11 yr from 143 000 t yr-1 in1988 to 181 000 t yr-1 in 1998. The major contributorsto the NH3 emission in South Korea are livestock andfertilizer application that account for 70 and 26% oftotal NH3 emission, respectively. The 11 × 14 km (0.125° long. × 0.125° lat.) grid distribution of emission of ammonia shows an maximum in the Yochon area due to the largest fertilizer factory and relatively wide regions of high NH3 emission in thenorthwestern part of South Korea due to a great number of livestock. It is found that the nitrogen ratio of wet deposition of NH4 + to emission of NH3 in SouthKorea is averaged to be 0.45.  相似文献   
902.
903.
904.
905.
906.
The aim of this paper is to evaluate the role that agglomeration may have on vertical boundaries in exchanges associated with high transaction costs. Transaction cost economics identifies the presence of specific assets in stages of the value chain as the main driver of vertical integration. However, under the trustworthy and shared social milieu that agglomerated spaces may confer, neighboring firms can enjoy lower opportunism risk and communication costs. Therefore, we assume that even in the presence of specific assets, physically proximate firms are more likely to remain specialized and establish market exchanges. Empirical evidence in 10,186 establishments from the Spanish meat industry confirms these hypotheses, although it is found that the moderating role of agglomeration in the relationship between asset specificity and vertical integration has a limited geographical reach.  相似文献   
907.
The purpose of this study was to investigate how Taiwanese high‐tech firms' foreign direct investment (FDI) leads to agglomeration and competition among cities in China. By using social network analysis to analyze 1,111 subsidiaries affiliated with 270 multinational corporations (MNCs) during the years between 1988 and 2006 in 30 major Chinese cities, this study finds that: 1) agglomeration in Chinese cities falls into three primary categories: the hub cluster, the communication‐extended cluster, and the computer‐extended cluster. Among the aforementioned clusters, the hub cluster is the most critical in terms of firm location, and therefore is often a high‐priority investment site for Taiwanese high‐tech firms. 2) Chinese cities fall into four primary groups, or “blocks”: the core block, the coast block, the inland block, and the periphery block; these groups were determined by applying a structural equivalence analysis of which members of each type are in competition with one another. By linking the findings of the urban network characteristics to Chinese regional economic policies, this study provides guidance to aid executives in determining the optimal location for future FDI. Implications and suggestions for host country governments in terms of firms' investment strategies are also discussed.  相似文献   
908.
909.
Two soybean recombinant inbred line populations, Jinpumkong 2 × SS2-2 (J × S) and Iksannamulkong × SS2-2 (I x S) showed population-specific quantitative trait loci (QTLs) for days to flowering (DF) and days to maturity (DM) and these were closely correlated within population. In the present study, we identified QTLs for six yield-related traits with simple sequence repeat markers, and biological correlations between flowering traits and yield-related traits. The yield-related traits included plant height (PH), node numbers of main stem (NNMS), pod numbers per plant (PNPP), seed numbers per pod (SNPP), 100-seed weight (SW), and seed yield per plant (SYPP). Eighteen QTLs for six yield-related traits were detected on nine chromosomes (Chrs), containing four QTLs for PH, two for NNMS, two for PNPP, three for SNPP, five for SW, and two for SYPP. Two highly significant QTLs for PH and NNMS were identified on Chr 6 (LG C2) in both populations where the major flowering gene, E1, and two DF and DM QTLs were located. One other PNPP QTL was also located on this region, explaining 12.9% of phenotypic variation. Other QTLs for yield-related traits showed population-specificity. Two significant SYPP QTLs potentially related with QTLs for SNPP and PNPP were found on the same loci of Chrs 8 (Satt390) and 10 (Sat_108). Also, highly significant positive phenotypic correlations (P < 0.01) were found between DF with PH, NNMS, PNPP, and SYPP in both populations, while flowering was negatively correlated with SNPP and SW in the J × S (P < 0.05) and I × S (P < 0.01) populations. Similar results were also shown between DM and yield-related traits, except for one SW. These QTLs identified may be useful for marker-assisted selection by soybean breeders.  相似文献   
910.
The physicochemical properties of pigmented (Midorimochi, Jeokjinjubyeo, and Heukmichalbyeo) and non-pigmented (Hwayoungbyeo) rice varieties were investigated. Starch from non-pigmented rice consisted mainly of large polyhedral granules that were more loosely packed than those of the non-pigmented sample. Pigmented rice showed higher linoleic acid content (36–40%) and hydrolysis rate (63–79%) but lower oleic acid content (35–39%), blue value (0.05–0.17), and viscosity values than the non-pigmented one. Significantly higher mineral content, blue value, and pasting and viscosity values were observed in the Jeokjinjubyeo sample compared to those of the other pigmented rice samples. The Midorimochi variety, on the other hand, exhibited the highest total amino acid (816.82 ng mg−1) and sugar (0.15–3.35 μg g−1) contents and the lowest pasting and viscosity values. No substantial difference in the X-ray diffraction pattern was observed among the samples. Results of this study could serve as baseline information for the quality evaluation of three pigmented rice cultivars and provide a better understanding of their potential uses and food industry applications.  相似文献   
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