企业绿色债券发行的研究综述:影响因素与经济后果

自“双碳”目标提出以来,中国经济从高速增长转向追求高质量增长。绿色债券作为绿色金融体系的重要构成部分,有助于企业向经济与环境友好型转型。随着绿色债券市场的不断成长,企业绿色债券发行的相关研究日益丰富。本文分别从企业内外部两个方面归纳了绿色债券发行的影响因素,并进一步梳理了企业绿色债券发行的经济与环境影响。本文希望能为企业绿色债券相关问题的深入研究提供有益参考。

非水虻源微生物与武汉亮斑水虻幼虫联合转化鸡粪的研究

【目的】益生微生物在协助亮斑扁角水虻幼虫转化有机废弃物、提高其转化效率方面具有重要的作用,本研究针对非水虻源微生物,开展与水虻联合转化鸡粪的研究,以阐明外源微生物在水虻转化畜禽粪便中的作用,对其转化机制的研究及产业化生产具有重要意义。【方法】采用稀释涂平板的方法进行鸡粪堆肥和猪粪堆肥中细菌的分析,并将筛选到的细菌分别接种到无菌的鸡粪基质中与武汉亮斑水虻幼虫联合转化,通过称重法测定转化后武汉亮斑水虻及鸡粪的重量,评价转化效果及对幼虫的影响,然后将促进转化效果明显的菌株按不同比例进行复配,与武汉亮斑水虻幼虫联合转化新鲜鸡粪,分析复配菌剂对武汉亮斑水虻幼虫转化鸡粪的影响。【结果】结果显示R-07、R-09、F-03和F-06在促进武汉亮斑水虻幼虫生长和鸡粪转化的效果上最为显著。与对照组相比,水虻幼虫转化率分别提高了27.21%、15.00%、9.93%和16.29%;基质减少率分别提高了17.94%、10.42%、7.84%和9.27%。将这4株细菌配制复配菌剂与武汉亮斑水虻幼虫联合转化鸡粪,结果显示复配比例为R-07:R-09:F-03:F-06=4:1:1:1时效果最好,与空白对照相比,武汉亮斑水虻幼虫存活率提高了10.25%,幼虫虫重增加了28.41%,幼虫转化率增加了30.46%,鸡粪减少率增加了7.69%。【结论】添加通过筛选优化的非水虻来源的微生物复合菌剂能够促进水虻高效转化鸡粪,研究结果有助于改善现有的武汉亮斑水虻幼虫转化体系,为开发新型的联合转化工艺、更加有效地处理畜禽粪便奠定基础。

Microstructural evolution and stress relaxation cracking mechanism for Super304H austenitic stainless steel weld metal

The pre-compressed CT technique was used to quantitatively investigate the formation of stress relaxation cracks under different tensile residual stresses and aging time in Super304H austenitic stainless steel weld metal.The statistical results revealed that intergranular cracks could occur within 2000 h under 650℃ when the residual stress was applied with greater than 18 KN pre-compression force.Detailed grain interior and boundary analyses showed that the growth of intragranular Cu-rich particles could induce a strong grain interior,and the intergranular Nb(C,N)carbides were one of the causes to crack under short-term aging time.For long-term aging time conditions,the intergranular M_(23)C_(6)carbides were more susceptible to crack than intergranular Nb(C,N)carbides.Finally,the mechanism responsible for stress relaxation cracking formation was carefully illustrated for the weld metals after short-term aging and long-term aging,respectively.