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1.
In the high technology industry, small and medium sized technology enterprises (SMSTEs) play a pivotal role in advancing the whole industry. To achieve sustainable development, they need to extend their scope of business activities beyond a national view and exploit international market actively to meet international competitions that increase quickly in the form of allocating resources within the scope of the world. However, the SMSTEs are also facing risks associated with themselves during the process of exploiting international market owing to their own restrictions, so what they should do is to consider risk evaluations in exploiting the international market.  相似文献   
2.
The methane concentration profile from -1.5m depth in soil to 32m height in air was measured in alpine steppe located in the permafrost area. Methane concentrations showed widely variations both in air and in soil during the study period. The mean concentrations in atmosphere were all higher than those in soil, and the highest methane concentration was found in air at the height of 16m with the lowest concentration occurring at the depth of 1.5m in soil. The variations of atmospheric methane concentrations did not show any clear pattern both temporally and spatially, although they exhibited a more steadystable state than those in soil. During the seasonal variations, the methane concentrations at different depths in soil were significantly correlated (R^2〉0.6) with each other comparing to the weak correlations (R^2〈0.2) between the atmospheric concentra- tions at different heights. Mean methane concentrations in soil significantly decreased with depth. This was the compositive influence of the decreasing production rates and the increasing methane oxidation rates, which was caused by the descent soil moisture with depth. Although the methane concentrations at all depths varied widely during the growing season, they showed very distinct temporal variations in the non-growing season. It was indicated from the literatures that methane oxidation rates were positively correlated with soil temperature. The higher methane concentrations in soil during the winter were determined by the lower methane oxidation rates with decreasing soil temperatures, whereas methane production rates had no reaction to the lower temperature. Relations between methane contribution and other environmental factors were not discussed in this paper for lacking of data, which impulse us to carry out further and more detailed studies in this unique area.  相似文献   
3.
There is an obvious departure from the regional equilibrium of developments between the upper and lower reaches of the Pearl River in Guangdong, which resulted in "the effects of contra-geography-grads development". It is mainly because the upriver mountainous areas have been deeply stuck in industrialization delay and marginalization plights, so that nearly 40 million local people have conceived a dream to get rid of "the vicious circle of poverty" by speeding up industrial development. But the problem is that such industrialization efforts on a large scale in mountainous areas are encountering the bottleneck of environmental capacity that strictly limits industrial emissions along the upper reaches of any water system. As a solution, an institutional arrangement called "the Local Area Quotas for Industrial Emissions along the Pearl River" is put forward supposed to give corresponding compensation to the rights of industrial development yielded by some areas with lower environmental capacity through the distribution and trading of IDQs.  相似文献   
4.
应联合国环境规划署技术、工业与经济司(UNEP DTIE)的要求,一项旨在确定由地方职权部门草拟并贯彻的当地21世纪议程中旅游所处地位的调查研究1已经完成.这次的调研、部分吸收了一些地方社区2的经验,这些社区旅游活动层次各不相同,但是都是采用了本地21世纪议程.调研内容包括:◆旅游在21世纪地方议程中的地位;◆公在解决旅游(在目的地)产生的问题和对旅游战略解释中.21世纪地方议程的作用;◆旅游所涉及到的这种办法的最大限度;◆为提高与旅游相关的方方面面.对21世纪地方议程的建议. 在旅游目的地,旅游对当地社区的一个主要影响是:它可能会对地方的发展起到积极作用.它也能够创造工作机会和收入然而,旅游威胁着这些目的地的自然与文化遗产,以及当地的社会平衡.对环境、景观、文化多样性及财富的伤害、最终会对旅游自身产生负面影响.  相似文献   
5.
The organic matter in tropospheric aerosol plays an important role in atmospheric physical and chemical processes. The bulk of organic matter, representing a significant proportion of the total suspended particulate (TSP) mass, is bound to polymeric material whose structure and properties are largely unknown. Here we used thermodesorption gas chromatography/mass spectrometry (Td- GC/MS) to study organic compounds of low molecular mass and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) to characterize the chemical structure of macromolecules in TSP samples collected in di erent seasons from di erent sites in Guangzhou. n-Alkanes, fatty acids and nitriles were the predominant compounds in the thermodesorption products, whereas aromatics, fatty acids, nitriles and n-alkanes/alkenes were the major compounds in the pyrolysates. The results indicated that aromatics were main units in macromolecules. The fatty acids and nitriles formed from carboxylic ammonium salts were detected in both thermodesorption products and pyrolysates at a certain concentration, indicating the importance of these compounds in TSP formation. The TSP source mainly determined the occurrence of compounds in samples from urban, suburban and forest sites, whereas the TSP source and formation process maybe controlled the seasonal variation in compounds detected. High levels of nitriles in summer samples from suburban and forest sites coincide with the release of ammonium from the land and of fatty acids from vegetation at these sites.  相似文献   
6.
A reliable and sensitive competitive real-time fluorescent quantitative immuno-PCR (RTFQ-IPCR) assay using a molecular beacon was developed for the determination of trace fluoranthene (FL) in the environment. Under optimized assay conditions, FL can be determined in the concentration range from 1 fg/mL to 100 ng/mL, with y = 0.194x + 7.859, and a correlation coe cient of 0.967 was identified, with a detection limit of 0.6 fg/mL. Environmental water samples were successfully analyzed, recovery was between 90% and 116%, with intra-day relative standard deviation (RSD) of 6.7%–12.8% and inter-day RSD of 8.4%–15.2%. The results obtained from RTFQ-IPCR were confirmed by ELISA, showing good accuracy and suitability to analyze FL in field samples. As a highly sensitive method, the molecular beacon-based RTFQ-IPCR is acceptable and promising for providing reliable test results to make environmental decisions.  相似文献   
7.
A combined process consisting of a short-cut nitrification (SN) reactor and an anaerobic ammonium oxidation upflow anaerobic sludge bed (ANAMMOX) reactor was developed to treat the diluted effluent from an upflow anaerobic sludge bed (UASB) reactor treating high ammonium municipal landfill leachate.The SN process was performed in an aerated upflow sludge bed (AUSB) reactor (working volume 3.05 L),treating about 50% of the diluted raw wastewater.The ammonium removal efficiency and the ratio of NO 2 N to NOx-N in the effluent were both higher than 80%,at a maximum nitrogen loading rate of 1.47 kg/(m 3 ·day).The ANAMMOX process was performed in an UASB reactor (working volume 8.5 L),using the mix of SN reactor effluent and diluted raw wastewater at a ratio of 1:1.The ammonium and nitrite removal efficiency reached over 93% and 95%,respectively,after 70-day continuous operation,at a maximum total nitrogen loading rate of 0.91 kg/(m 3 ·day),suggesting a successful operation of the combined process.The average nitrogen loading rate of the combined system was 0.56 kg/(m 3 ·day),with an average total inorganic nitrogen removal efficiency 87%.The nitrogen in the effluent was mostly nitrate.The results provided important evidence for the possibility of applying SN-ANAMMOX after UASB reactor to treat municipal landfill leachate.  相似文献   
8.
本文考察:1)6个充满活力的亚洲经济实体—香港、韩国、马来西亚、新加坡、台湾和泰国的政府如何对《蒙特利尔议定书》所提出的挑战做出反应,以削减它们的臭氧耗损物质如氯氟烃(CFC)和甲基氯仿(MC)的消费量;2)这些经济实体中的电子公司如何解决在其清洗操作中代替CFC-113和MC所涉及的技术问题和其它问题。它说明不同的国家控制战略和政策框架能如何形成对节约和循环利用的刺激;实行定量限制的国家一直十分有效地削减CFC消费量。一旦实行配额,政府就很容易设计一种分配制度;使它们能获得大量配额租金来资助那些旨在有利于淘汰工作的措施。通过节约措施实现的大幅度削减只增加相当少的成本。本文也认为《蒙特利尔议定书》的贸易条款和美国的CFC税已经对这些高度面向出口的经济实体的政府对策和公司业务产生重要影响。 本文列举了可用于CFC替代的主要备选方案,并根据实地调查,确认了其迅速采用的某些技术、信息和资金障碍。同时,它说明了许多电子公司如何成功地克服这些障碍。虽然目前已取得了颇大进展,但随着替代进程的推移,边际成本可能更急剧地上升:简而言之,最后10%的削减可能远比前90%更难。 不同国家中各公司阅历长短和技术能力水平的差异,强烈地决定它们在寻找CFC代用品方面的积极性和创造  相似文献   
9.
Intergenerational conflict coordination is the fundamental requirement and core of sustainable development. In this paper, through the analysis of the future generations-oriented management mechanisms for intergenerational conflict, the idea of mechanisms and institution building for the coordination and management of intergenerational conflict is put forward. Furthermore, the future generations-oriented virtual negotiation support system (NSS) for intergenerational conflict is developed, built on the analysis of the process simulation of intergenerational wealth transfer, intergenerational equilibrium allocation of resources, and strategies for the mitigation and avoidance of intergenerational conflict, through the application of advanced IT technology. The virtual NSS for intergenerational conflict is helpful to the practical application of the sustainable development theory; on the other hand, it can be applied directly to the intergenerational equilibrium allocation of resources, national economic accounting, formulation of sustainable development strategies and other urgent national economic and social development issues. Finally, the sustainable development theory can be enriched and extended. Therefore, the development of the future generations-oriented virtual NSS for intergenerational conflict has certain theoretical and practical effects on the theory of sustainable development.  相似文献   
10.
Taking 248 A-share manufacturing listed companies in 2006 Shanghai Stock Exchange as example, using "index method" to measure level of environmental protection information disclosure, this paper examines the factors influencing level of environmental protection information disclosure. The findings show that the disclosure level has improved, but the overall level is still low and unable to satisfy information users; there is positive correlation between corporate size, industry type, accounting firm's type and corporate environmental disclosure index. The companies of large scale and heavy pollution and those audited by international "Big 4" and domestic "Big 10" accounting firms have a high level of environmental disclosure, while the profitability and financial leverage has no impact on the disclosure level. Finally some suggestions are put forward to establish environmental information disclosure system in China.  相似文献   
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