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411.
Global climate issues and a looming energy crisis put agriculture under pressure in Sub-Saharan Africa. Climate adaptation measures must entail sustainable development benefits, and growing crops for food as well as energy may be a solution, removing people from hunger and poverty without compromising the environment. The present study investigated the feasibility of using non-food parts of cassava for energy production and the promising results revealed that at least 28% of peels and stems comprise dry matter, and 10 g feedstock yields >8.5 g sugar, which in turn produced >60% ethanol, with pH ≈ 2.85, 74-84% light transmittance and a conductivity of 368 mV, indicating a potential use of cassava feedstock for ethanol production. Thus, harnessing cassava for food as well as ethanol production is deemed feasible. Such a system would, however, require supportive policies to acquire a balance between food security and fuel.  相似文献   
412.
通过单因素试验和正交试验确定了实验室保藏的壬基酚降解菌株沙雷氏菌(Serratiasp.LJ)的最佳产酶条件:以壬基酚、硫酸铵为碳源、氮源,培养基初始pH为6.8,培养温度为30℃,种子活化时间为24h,接种量为3%(体积分数)。在此条件下培养72h后,最高酶活力为1.314IU/mL,是优化前的1.77倍。  相似文献   
413.
改革开放30多年来,中国的食品工业有突飞猛进的发展,食品企业的生产能力大幅提升,但中国食品工业仍然存在着诸如食品质量体系不健全、食品安全隐患大等问题.分析了我国食品工业可持续发展生产的背景,然后就河南、四川、青海三省的食品企业可持续发展生产状况做了问卷分析.根据问卷分析结果,从政府层面、企业层面、社会层面提出促进我国食品工业可持续发展的建议.  相似文献   
414.
Kinetics of H2 production from liquid swine manure supplemented with glucose by mixed anaerobic cultures was investigated using batch experiments under four different pH conditions (4.4, 5.0, 5.6, and uncontrolled). The temperature for the experiments was controlled at 37 ± 1°C and the length of experiments varied between 50 and 120 hours, depending upon the time needed for completion of each individual experiment. The modified Gompertz model was evaluated for its suitability for describing the H2 production potential, H2 production rate, and substrate consumption rate for all the experiments. The results showed that the Gompertz model could adequately fit the experimental results. The effect of pH was significant on all kinetic parameters for H2 production including yield, production rate and lag time, and the substrate utilization rate. The optimal pH was found to be 5.0, at which a maximum H2 production rate (0.64 L H2/h) was obtained, and deviation from the optimal pH could result in substantial reductions in H2 production rate (0.32 L H2/h for pH 4.0 and 0.43 L H2/h for pH 5.6). The results also showed that if pH was not controlled for the batch fermentation process, the substrate utilization efficiency could steeply decrease from 98.8% to 33.7%.  相似文献   
415.
Many of the numerous difficult issues facing the world today involve relationships entailing trade‐offs and synergies. This study quantitatively assesses some alternative scenarios using integrated assessment models, and provides several indicators relating to sustainable development and climate change, such as indicators of income (per capita GDP), poverty, water stress, food access, sustainable energy use, energy security, and ocean acidification, with high consistencies among the indicators within a scenario. According to the analyses, economic growth helps improve many of the indicators for sustainable development. On the other hand, climate change will induce some severe impacts such as ocean acidification under a non‐climate intervention scenario (baseline scenario). Deep emission reductions, such as to 2°C above the pre‐industrial level, could cause some sustainable development indicators to worsen. There are complex trade‐offs between climate change mitigation levels and several sustainable development indicators. A delicately balanced approach to economic growth will be necessary for sustainable development and responses to climate change.  相似文献   
416.
成都市餐厨垃圾产量分析预测及监管体系建设研究   总被引:1,自引:0,他引:1  
整理汇总了成都市中心城区及郊县餐厨垃圾产生和收运现状,对其产量作出预测;在此基础上提出适合成都市自身情况的餐厨垃圾监管体系构建设想。  相似文献   
417.
阐述了循环经济的内涵,分析了煤炭企业传统生产模式存在的问题,指出煤炭企业实施循环经济生产模式的必要性,提出我国煤炭企业建立循环经济生产模式的基本思路。即建立以煤炭企业为中心的小循环生产模式,以大型煤炭生产基地为中心的中循环生产模式和以社会为中心的大循环生产模式,对我国煤炭企业实施循环经济的生产模式具有指导意义。  相似文献   
418.
本文确认了全球社会-生态问题(过度消费,道德危机)的主要根源并提出了新的可持续发展的愿景,重点要关注精神、道德、心理、生理和人的智力开发(而代替以消费为导主的理念)。讨论了人类发展指标不足所涉及到的因素(寿命预期、人均国内生产总值),提出了测量人类可持续发展的替代指标,即:健康人口的比例。生态效率也被建议作为转化可持续发展的必要条件,人的精神,根据生态中心立场(社会-生态幸福)。通过适当的教育和体制政策而实现环境和人类健康、公平和整个人类的发展。  相似文献   
419.
Translating policies about sustainable development as a social process and sustainability outcomes into the real world of social–ecological systems involves several challenges. Hence, research policies advocate improved innovative problem-solving capacity. One approach is transdisciplinary research that integrates research disciplines, as well as researchers and practitioners. Drawing upon 14 experiences of problem-solving, we used group modeling to map perceived barriers and bridges for researchers’ and practitioners’ joint knowledge production and learning towards transdisciplinary research. The analysis indicated that the transdisciplinary research process is influenced by (1) the amount of traditional disciplinary formal and informal control, (2) adaptation of project applications to fill the transdisciplinary research agenda, (3) stakeholder participation, and (4) functional team building/development based on self-reflection and experienced leadership. Focusing on implementation of green infrastructure policy as a common denominator for the delivery of ecosystem services and human well-being, we discuss how to diagnose social–ecological systems, and use knowledge production and collaborative learning as treatments.  相似文献   
420.
城市生活垃圾的成分及特性随着季节和人类在不同季节的生活习惯而变化,针对我国北方城市研究了一年中不同季节的城市生活垃圾成分特点,对影响厌氧发酵过程的相关成分如总有机碳(TOC)、总氮(TN)、蛋白质、脂肪和还原糖等进行了测定分析。通过厌氧消化实验,测得不同季节城市生活垃圾pH值、日产气量、沼气甲烷含量、甲烷累积量、挥发性脂肪酸(VFAs)和氧化还原电位(ORP)等参数的变化规律,分析相应变化的影响因素。结果表明,二、三季度的含水率分别为64.81%和67.50%,高于一、四季度,一季度发酵原料中蛋白质和脂肪含量分别为12.56%和8.86%,明显高于其他3个季度。一季度甲烷累积量最高,达到17616mL,单位发酵原料的产气量为204.8mL/g,也是4个季度中最高的,说明蛋白质、脂肪等有机成分含量对厌氧发酵过程及结果影响比较明显。为进一步的城市生活垃圾厌氧消化制取生物燃气的工艺条件提供依据。  相似文献   
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