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101.
Removal of phenanthrene (PHE) from aqueous solution by adsorption onto quaternary ammonium surfactant modified peat was studied. The results show that surfactant modification enhanced the PHE adsorption capacity of peat. Low temperature and neutral pH favored PHE adsorption. Peat modified with long carbon chain surfactant performed better than peat modified with short carbon chain surfactant. The magnitude of PHE adsorption capacity followed the order of MP-HPB>MP-HTAB>MP-TBAB>RP, ranged from 924 to 1,228 μg g(-1). A negative trend between adsorption capacity (y) and (O+N)/C ratio of biosorbent (x) was observed (y = -1,369.6x + 2,176), which confirmed the negative effect of polarity on polycyclic aromatic hydrocarbon (PAH) removal. The study provides a guide to modify raw materials to enhance adsorption of hydrophobic organics.  相似文献   
102.
The Informational Role of Stock and Option Volume   总被引:8,自引:0,他引:8  
This article analyzes the intraday interdependence of orderflows and price movements for actively traded NYSE stocks andtheir Chicago Board Options Exchange (CBOE)-traded options.Stock net trade volume (buyer-initiated volume minus seller-initiatedvolume) has strong predictive ability for stock and option quoterevisions, but option net trade volume has no incremental predictiveability. This suggests that informed investors initiate tradesin the stock market but not in the option market. On the otherhand, both stock and option quote revisions have predictiveability for each other. Thus, while information in the stockmarket is contained in both quote revisions and trades, informationin the option market is contained only in quote revisions.  相似文献   
103.
To design selling positions that appeal to both new and incumbent salespersons, management needs to understand salespersons' preferences for job characteristics. The study reported here exemplifies an effort to operationalize salespersons' preferences for job and task characteristics that takes account of both career stage and gender. Findings indicate that salespeople in the sample prefer salary-based compensation and that female salespeople prefer sales jobs that are fixed in location.  相似文献   
104.
This paper examines the volume distribution of option trade prices that occurs when the underlying stock price remains constant. The width of these option trade price bands provides direct evidence on the law of one price and the redundancy of options assumed in many option models. We find that index option bands are narrower than equity option bands. Furthermore, for both equity and index options, puts have narrower bandwidths than calls. In general, option price bandwidth is narrow and can be explained by the minimum price movement allowed by the Chicago Board Options Exchanges (CBOE). This supports the single price law and the redundancy assumption. The existence of bid/ask quotes on the option does not materially affect the above results although it does alter the frequency of multiple option trade prices for a given underlying stock price. We note that over 53% of option trading volume occurs without bid/ask quotes on the CBOE compared to less than 15% a decade ago. Our results suggest that the effective bid/ask spread on options is probably no larger than the minimum price movements allowed by the CBOE. Furthermore, the need for the liquidity services of market makers may be declining if the decline in quoting activity stems from cross trading (i.e. trades not involving market makers).  相似文献   
105.
Little attention has been paid in the literature to the impact of different investment horizons on the portfolio compositiondespite its importance to portfolio managers. One exception isthe study by Gunthorpe and Levy (1994) on the U.S. stock market.Our paper extends the same study to the stock markets of Japan,Hong Kong and Korea. Using 40 individual stocks in each market,our results support those of Gunthorpe and Levy (1994) in thatthe composition of an optimal portfolio depends heavily on theinvestment horizon. When the investment horizon lengthens, theproportion of defensive stocks becomes larger while that ofaggressive stocks becomes smaller.  相似文献   
106.
Do the Forward Sales of Real Estate Stabilize Spot Prices?   总被引:1,自引:0,他引:1  
We examine the effect of forward sale (pre-sale) activities on the volatility of spot prices in the real estate market. The abundance of pre-sales data and major changes in regulatory control on the pre-sale market during the 90's in Hong Kong allow us to undertake empirical tests using Hong Kong's real estate data. Our results show that the volatility of spot prices increased significantly after forward sales were severely dampened by regulatory control measures introduced in 1994, but decreased again when the measures were partly relaxed in 1998. The results contribute to the long lasting debate on whether the introduction of a futures market reduces the volatility of spot prices. Previous studies were mainly conducted in markets with low transaction costs, notably financial markets. By utilizing the unique regulatory changes in the pre-sale market of Hong Kong, we are able to conduct an experiment on the conditional volatility of spot prices in a high information-cost environment, thereby shedding light on the important role of forward housing contracts in providing price expectation information for spot trading.  相似文献   
107.
Household Finance   总被引:17,自引:0,他引:17  
The study of household finance is challenging because household behavior is difficult to measure, and households face constraints not captured by textbook models. Evidence on participation, diversification, and mortgage refinancing suggests that many households invest effectively, but a minority make significant mistakes. This minority appears to be poorer and less well educated than the majority of more successful investors. There is some evidence that households understand their own limitations and avoid financial strategies for which they feel unqualified. Some financial products involve a cross‐subsidy from naive to sophisticated households, and this can inhibit welfare‐improving financial innovation.  相似文献   
108.
Global sourcing strategy and sustainable competitive advantage   总被引:1,自引:0,他引:1  
Global sourcing strategy has been one of the most hotly debated management trends in the last 20 years. In its early years, global sourcing was examined mostly from “in-house” development and procurement perspectives; and in the last several years, research focus has shifted to “outsourcing” activities. Along with this shift from internal to external focus on global sourcing, many researchers and business practitioners have applied a core competency argument to justify increased levels of outsourcing activities on a global basis. Although the beneficial aspects of outsourcing are assumed in most cases, no consensus exists in reality as to the effect of outsourcing. Furthermore, the increased instability of the exchange rate environment in the last several years has also led to increased difficulties in managing globally scattered operations that were once fashionable in the 1980s-90s under the rubric of global strategy. In this article, the authors explore potential limitations and negative consequences of outsourcing strategy on a global scale.  相似文献   
109.
There has been copious research work on the development of house price models and the construction of house price indices. However, results in some studies revealed that the accuracy of such indices could be subject to selection bias when using only information from a sample of sold properties to estimate value movements for the entire housing stock. In particular, estimated house price appreciation is usually systematically higher among properties that change hands more frequently. It therefore suggests that the determination of important factors affecting the transaction frequency or intensity of a housing unit should be a more fundamental research question. This paper examines the possible factors that determine the popularity of residential unit by means of a repeated sales pattern. The Poisson regression model and event history analysis techniques are employed to assess the effect of attributes on transaction frequency and intensity. The event history analyses technique can take account of transaction-specific as well as time-dependent covariates, and therefore is recommended for analyzing repeated sales data in a real estate market. All transaction records during the period 1993–2000 from the Land Registry of one of the most popular residential estates in Hong Kong were used to illustrate the method. Unlike a response to favorable transaction price, good quality units do not necessarily inherently display a high transaction frequency. Rather, units of average quality are more likely to be transactionally active.  相似文献   
110.
Abstract

Ulrich Beck fundamentally transformed our way of thinking about human interdependence through his three core theses on risk, individualisation and cosmopolitanisation. However, two commonly observed deficiencies in Beck’s grand theory were its Eurocentric orientation and a lack of empirical grounding. Based on 5 focus groups and 14 interviews with participants of the emerging Clean Food Movement in China, this paper extends the Beckian discussion outside Europe. Through examining how individuals understand both ‘traditional’ and ‘new’ risks associated with contemporary food consumption, this paper demonstrates that in the face of unpredictable and incalculable harms, risks are not seen as a ‘thing’, but are translated into ‘causal relations’. Subsequently, for Chinese stakeholders, the best way to safeguard food risks is to enact more visible and functioning interdependent relations in the food system. This in turn has given rise to new forms of communities which cut across conventional geographic, socio-economic and political boundaries. The paper deepens a Beckian theorisation in two ways. First, it demonstrates that the ‘enabling’ effect of risk towards a cosmopolitan society is not limited to obvious global crises, such as climate catastrophes and financial meltdown. In fact, the mundane yet intimate concern of putting ‘good’ food in one’s dinner bowl already presses actors to form new social solidarities that are cosmopolitan in nature. Second, it goes beyond Beck’s assertion that the risk society has culminated in a cosmopolitan moment, and explores how a performative cosmopolitan community reshapes the ‘relations of definition’ to mitigate risks on the ground.  相似文献   
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