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81.
ABSTRACT

Arguments are advanced for two ways in which we can avoid the reckless endangerment of future people in the governance of solar radiation management (SRM) research, which could happen through lock-in to SRM deployment from research. SRM research is at an early stage, one at which the mechanisms of lock-in could start to operate. However, lock-in fit to endanger future people could be slowed or stopped through targeted governance. Governance of SRM research that does not include provisions to detect, slow, or stop lock-in fails the test of an intergenerationally adequate precautionary principle, and research governed without these provisions cannot itself be justified as a precaution against the impacts of climate change.  相似文献   
82.
This article reports an innovative integrated system utilizing solar energy as power for decentralized wastewater treatment, which consists of an oxidation ditch with double channels and a photovoltaic (PV) system without a storage battery. Because the system operates without a storage battery, which can reduce the cost of the PV system, the solar radiation intensity affects the amount of power output from the PV system. To ensure that the power output is sufficient in all different weather conditions, the solar radiation intensity of 78 W/m 2 with 95% confidence interval was defined as a threshold of power output for the PV system according to the monitoring results in this study, and a step power output mode was used to utilize the solar energy as well as possible. The oxidation ditch driven by the PV system without storage battery ran during the day and stopped at night. Therefore, anaerobic, anoxic and aerobic conditions could periodically appear in the oxidation ditch, which was favorable to nitrogen and phosphate removal from the wastewater. The experimental results showed that the system was efficient, achieving average removal efficiencies of 88% COD, 98% NH 4 + -N, 70% TN and 83% TP, under the loading rates of 140 mg COD/(g MLSS·day), 32 mg NH 4 + -N/(g MLSS·day), 44 mg TN/(g MLSS·day) and 5 mg TP/(g MLSS·day).  相似文献   
83.
The ISCC technology representing an integrated solar combined cycle and the economic assessment of ISCC are investigated. Comparisons conducted by theoretical calculation method among two cases, that is, an integrated solar combined cycle system (ISCCS) and a combined cycle gas turbine system (CCGTS) show that ISCCS provides the best solution with the highest efficiency of heat to electricity among them. The results reflected by theoretical calculation also reveal that ISCCS is beneficial to energy saving and emission reduction. Due to the great advantages of ISCC, comprehensive analysis on the basic conditions for building ISCC power plants is analyzed in detail.  相似文献   
84.
黄河巨洪发生时间规律的讨论   总被引:3,自引:0,他引:3  
本文讨论了黄河巨洪发生的三个时间规律。一是巨洪一般发生在太阳活动的峰年或谷年;二是巨洪发生在甘、新、蒙交接区7级以上大震后一年内;三是巨洪发生在重合于25年周期的年份(从1933年算起),以及重合于这个周期的公度性年份和黄金分割年份。另外对太阳活动和巨洪的相关机制和大震与巨洪之间的相关机制也作了讨论。  相似文献   
85.
Constructed wetlands are widely used all over the world for the treatment of municipal wastewaters, which are characterized by high concentrations of pathogens. The objectives of this study were (1) to study the effect of solar radiation and temperature on the ability of a constructed wetland to reduce the concentration of total coliforms (TC), and (2) to evaluate the relationship between the presence of Salmonella spp. in the outflow and the concentration of TC. The results of this study showed that under Mediterranean environmental conditions, the percentage reduction in coliforms was lower during winter compared to all other seasons. Maximum removal of coliforms was achieved under conditions of high solar radiation and temperature. In addition, solar radiation was found to play a greater role in coliform die-off at low temperatures than at high temperatures. Finally, it was found that the probability of Salmonella spp. appearance in the outflow of the wetland was related to the concentration of TC. The increase in coliform bacteria in the effluents also increased the chances of Salmonella appearance. The risk of Salmonella spp. appearance in the outflow is minimized when the concentration of TC is below 102/100 mL.  相似文献   
86.
This article presents a case study of a project which provides photovoltaic-based rural electrification in the state of Alagoas in northeastern Brazil. The project, the Luz do Sol Programme (LdS), was initiated in mid-1996 by the Golden Genesis Company (Golden) and the Fundação Teotônio Vilela (FTV). The article emphasizes some noteworthy characteristics of the project: the partnership between US commercial and Brazilian philanthropic interests; the financial aspect, a dedicated line of credit requiring only the equipment itself as security; and the local ownership and management of system operations, collections, and routine maintenance.
In 1996, the Golden Genesis Company had developed a central battery charging system to bring the price of electrification within the range of the rural poor; it financed the US content of the systems, with the Bank of the Northeast of Brazil (BN) financing the Brazilian content. The article traces the long and arduous path to establish the programme, including both bureaucratic and technical challenges. These difficulties brought the project to an impasse in August of 1998, and Golden withdrew. FTV then re-negotiated the agreement with BN, changing the technical approach to individual solar home systems. This improved the situation, and the project has since enjoyed 100% loan repayment rates from the entrepreneurs. In June 1999, BP/Solarex became FTV's new commercial partner. The project currently shows promise of becoming the commercially viable programme originally envisaged by Golden, with commercial and technical decision-making at the local level.  相似文献   
87.
In view of the increasing interest in the development and dissemination of technologies for harnessing new and renewable sources of energy in India, there have also been some efforts towards their use in the domestic lighting sector. However, the cumulative number of Solar Photovoltaic (SPV) lighting systems such as SPV lanterns and solar home lighting systems in India is far below their theoretical potential despite government subsidy programmes. One of the major barriers is the high capital investment in these systems. The Clean Development Mechanism (CDM) provides industrialized countries with an incentive to invest in emission reduction projects in developing countries to achieve a reduction in CO2 emissions at lowest cost that also promotes sustainable development in the host country. SPV lanterns and solar home lighting systems could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable rural development. However, only two SPV projects have been submitted under the CDM so far. This study assesses the maximum theoretical as well as the realistically achievable CDM potential of SPV lanterns and solar home lighting systems in India. The SPV lantern project is financially viable at a certified emissions reductions (CER) price of 34 € whereas the solar home lighting project is financially viable at a CER price of 46 €. While the maximum mitigation volume is about 35 million tonne CO2 on an annual basis, an estimate of achievable CER levels is done using the past diffusion trends of SPV systems. We find that annual CER volumes could reach 0.8 to 2.4 million by 2012 and 5.6 to 13.6 million by 2020. This would require that the government sets the subsidy level for SPV lighting systems at a level that allows them to become viable with the CER revenue. From a macro-economic point of view this makes sense if the sustainability benefits are deemed sufficiently high to warrant promotion of this type of project.
Axel MichaelowaEmail:
  相似文献   
88.
We propose asymmetric angular-linear multivariate regression models, which were motivated by the need to predict some environmental characteristics based on some circular and linear predictors. A measure of fit is provided through the residual analysis. Some applications using data from solar energy radiation experiment and wind energy are given. Received: September 2003 / Revised: February 2005  相似文献   
89.
冯利华 《灾害学》1998,13(2):71-74
根据大量洪水和有关资料,从太阳活动、行星运行和地球系统等方面,分析了形成浙江洪水的物理因素,为洪水预测提供了一定的理论依据.  相似文献   
90.
TiO_2太阳能光催化降解有机污染物的研究进展   总被引:2,自引:0,他引:2  
以太阳能为激发光源的 Ti O2 光催化氧化技术是一项极具运用前景的绿色环保技术。简要介绍了 Ti O2 光催化氧化的原理、催化剂 Ti O2 的制备研究、Ti O2 太阳能反应器的研制以及该项技术在有机污染物降解中的应用  相似文献   
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