海上风电并网的经济调控——将欧洲经验应用于中国(下)

[目的] 文章为两篇论文中的第二部分,着眼于将欧洲国家的经济调控管理经验应用于中国电力系统当前面临的紧迫挑战之一——海上风电的有效并网。 [方法] 文章通过分析比较调控机制,总结出海上风电监管机制的五个要素：监管实体、有效非绑定程度、补贴管理方法、并网价格制定方法以及责任主体。结合中国国家发改委2015年颁布的电改“9号文”分析了中国并网调控机制及相关机制的变化,这些变化包括为中国并网企业引入单独的经济调控机制,可形象称之为“管住中间、放开两头”。 [结果] 为了确保实现调控目标,如：配置效率、成本效率以及服务质量(包括陆上风电和海上风电的及时连接和输送等),新的监管方法仍需改进。两篇论文中的第一部分基于对三个欧洲案例的研究结果表明：TSO模型、发电机模型和第三方模型,都可以应用于中国。但是考虑到欧洲和中国的差异,建议中国采用和其首要目标最匹配的调控模式。 [结论] 如果中国的首要目标是改善发电和并网的协调发展,激励输电投资,则TSO模式是最好的选择。需要注意的是,采用具有法律约束力的并网计划、并网公司对于未能及时并网确立明晰的责任以及减少弃风弃光的发生,通过独立的监管机构来实施这一模式至关重要。     

Canavalia brasiliensis seeds. Protein quality and nutritional implications of dietary lectin

This study reports on the performance of rats fed with diets based on Canavalia brasiliensis seed proteins. The raw seeds are not a good regime, causing the animals to lose weight, exhibiting low net protein utilization (NPU) values, high nitrogen excretion and macroscopic alterations of key internal organs. Heat treatment, but not dialysis of the seed meal, had a beneficial effect on the nutritional parameters. Feeding rats with a diet containing pure lectin showed a lower digestibility and NPU, a much higher dry matter and nitrogen excretion, impaired growth rate and small-intestine enlargement in comparison with rats pair-fed on egg-white protein. In addition, lectin was detected fully active against rabbit erythrocytes in the faeces of rats fed lectin-containing diets. It was suggested that the seed lectin acts as an antinutritive dietary component.     

Uptake and leaching of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine by hybrid poplar trees

The feasibility of remediating a high explosive, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), using hybrid poplar trees (Populus deltoides x nigra, DN34) was investigated. The fate, transport, and toxicity were determined. HMX was taken up by poplar cuttings from hydroponic solutions in long-term experiments (65 days) without evidence of toxicity. HMX was not toxic to actively growing hybrid poplar cuttings, even under saturated conditions. The measured log Kow for HMX was 0.19, less than other explosives, TNT, and RDX. However, the calculated transpiration stream concentration factor (TSCF) and root concentration factor (RCF) for HMX from an uptake study using radiolabeled [U-14C]HMX were 0.21 +/- 0.07 and 5.55 +/- 1.78 mL/g, respectively, both of which were intermediate between the values for TNT and ROX in previous reports. A 70% uptake of [U-14C]HMX was translocated and accumulated in leaves, and no metabolites were observed during a 65-day exposure using radiochromatography of plant tissue extracts. Most of the accumulated HMX (57%) in dried (fallen) poplar leaves was leached by deionized water after 5 days. Bioaccumulation in poplar trees and resolublization of HMX from leaves would be of significant ecological concern, and phytoremediation may not be warranted as a treatment option unless other processes occur under field conditions that degrade HMX to innocuous end products (e.g., photolysis, hydrolysis, or microbial degradation).