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1.
综述了固碳技术的研发历程,从资源化利用的角度看,CO2是一种大存量的“碳源”,化学固碳兼具碳减排和资源化的优势,是未来固碳技术的重点发展方向。基于化学固碳技术存在的问题及已形成的技术成果,将CO2资源化利用工艺与现有新材料合成工艺相结合,提出了以CO2为基础原料深度延伸产业链生产聚碳酸酯,并形成多元化产品结构、具备工业化实施条件的新型固碳工艺。针对新工艺主要涉及到的CO2合成尿素、尿素法DMC、酯交换法DPC、异丙苯法苯酚工艺、离子交换树脂法BPA合成工艺及非光气法PC等生产过程,进行了技术可行性分析。  相似文献   
2.
ABSTRACT

Many planning agencies worldwide now see climate change response as unavoidable. This paper proposes that a central task for contemporary planning theory is to guide planning practice as it develops multi-dimensional responses. We examine three theoretical constructs: anticipatory governance, legitimacy and social-ecological resilience. We argue that each conceptualises challenges climate change presents to planning practice, while providing theoretically informed options for responses. Building on this, we utilize Friedmann’s [2008. “The Uses of Planning Theory: A Bibliographic Essay.” Journal of Planning Education and Research 28 (2): 247–257. doi:10.1177/0739456X08325220] tasks for planning theory as a framework to assess the utility of planning theories to guide climate change response through practice. Associated issues are discussed, including the influence of translatable planning theories and the value of importing knowledge from other disciplines. The paper concludes that more sophisticated interplay between planning theory and practice may improve planning responses to the climate change threat. The need for planning theory to translate its conceptual discoveries to the domain of practice is key.  相似文献   
3.
Recirculating Aquaculture Systems (RAS) reduce water consumption by efficient filtration to maintain appropriate levels of accumulating compounds and sludge. Sludge is mechanically separated by drum filters and disposed of to the detriment of overall system water budgets. Dissolved nitrogen compounds are reduced via nitrification–denitrification filters, requiring commercial external carbon sources. The reuse of sludge after ozone pre-treatment may represent the next step in RAS optimization. The present study analyzes the content of sludge from RAS and tests ozonation as a pre-treatment for recycling as carbon source. The dissociative effect of ozone and the physicochemical changes due to ozonation lead to a significant increase in soluble carbon availability. Predominantly long-chain fatty acid (FA) (saturated and unsaturated) with 16 and 18 carbon atoms independently of the treatment were found in the profiles. Saturated FA concentrations in solution increased after 20, 40, and 60 min ozonation. The solid content of the sludge was practically unaffected by ozonation in terms of FA profile: only saturated FA slightly increases after 40 min treatment. The implications of these findings for denitrifying bacteria are discussed.

Abbreviations: Recirculating Aquaculture Systems (RAS); Advanced Oxidation Processes (AOPs)  相似文献   

4.
全液压动臂塔机动臂下放的势能以热能的形式损耗,使油液升温,对系统的工作性能造成不利影响。针对国内某型全液压动臂塔机,用蓄能器、泵/马达二次元件组合设计变幅机构能量回收再利用系统,以压力能方式对动臂下放的势能进行回收再利用。借助AMESim软件对该系统进行机液一体化建模仿真分析,并将蓄能器设定压力梯级配置。结果表明,该系统能够回收动臂势能并加以利用,且采用多个蓄能器设定压力梯级设置进行能量回收较为合理,势能回收率达56.07%,再利用率达75.56%。  相似文献   
5.
Catalase (CAT) is an antioxidant enzyme expressed by the CAT gene family and exists in almost all aerobic organisms. Environmental stresses induce the generation of reactive oxygen species (ROS) that eventually hinder plant growth and development. The CAT enzyme translates the hydrogen peroxide (H2O2) to water (H2O) and reduce the ROS levels to shelter the cells’ death. So far, the CAT gene family has not been reported in rapeseed (Brassica napus L.). Therefore, a genome-wide comprehensive analysis was conducted to classify the CAT genes in the rapeseed genome. The current study identified 14 BnCAT genes in the rapeseed genome. Based on phylogenetic and synteny analysis, the BnCATs belong to four groups (Groups I–IV). A gene structure and conserved motif analysis showed that Group I, Group II, and Group IV possess almost the same intron/exon pattern, and an equal number of motifs, while Group III contains diverse structures and contain 15 motifs. By analyzing the cis-elements in the promoters, we identified five hormone-correlated responsive elements and four stress-related responsive elements. Further, six putative bna-miRNAs were also identified, targeting three genes (BnCAT4, BnCAT6, and BnCAT8). Gene ontology (GO) enrichment analysis showed that the BnCAT genes were largely related to cellular organelles, ROS response, stimulus response, stress response, and antioxidant enzymes. Almost 10 BnCAT genes showed higher expression levels in different tissues, i.e., root, leaf, stem, and silique. The expression analysis showed that BnCAT1–BnCAT3 and BnCAT11–BnCAT13 were significantly upregulated by cold, salinity, abscisic acid (ABA), and gibberellic acid (GA) treatment, but not by drought and methyl jasmonate (MeJA). Notably, most of the genes were upregulated by waterlogging stress, except BnCAT6, BnCAT9, and BnCAT10. Our results opened new windows for future investigations and provided insights into the CAT family genes in rapeseed.  相似文献   
6.
Heat-integrated water network synthesis (HIWNS) has received considerable attention for the advantages of reducing water and energy consumptions. HIWNS is effective in water and energy sustainability. Mixed integer non-linear programming (MINLP) is usually applied in HIWNS. In this work, a novel nonlinear programming (NLP) was proposed for HIWNS by considering wastewater reuse and wastewater regeneration reuse. Integer variables are changed to non-linear equation by the methods for identifying stream roles and denoting the existence of process matches. The model is tested by examples with single and multiple regeneration unit problems. The testing results showed that the NLP is an alternative method for HIWNS with wastewater reuse and regeneration reuse.  相似文献   
7.
为预测机场场面运行安全态势,提出一种本体和贝叶斯网络(BN)集成建模方法来评估跑道侵入严重度值,并进行最优风险把控措施决策。首先,基于威胁与差错管理(threat and error management,TEM)模型构建跑道侵入态势评估领域本体并完成BN转换;然后,利用融合本体语义信息的BN模型学习历史数据,提出跑道侵入事故征候严重度值评价指标;最后,分析实际案例并进行最优风险把控决策。结果表明,跑道侵入态势评估系统能够有效地描述事故征候的形成进而演化为跑道侵入事故的动态过程,并为最优风险控制决策提供客观依据。  相似文献   
8.
Computer‐Interpretable Guidelines (CIGs) are the dominant medium for the delivery of clinical decision support, given the evidence‐based nature of their source material. Therefore, these machine‐readable versions have the ability to improve practitioner performance and conformance to standards, with availability at the point and time of care. The formalisation of Clinical Practice Guideline knowledge in a machine‐readable format is a crucial task to make it suitable for the integration in Clinical Decision Support Systems. However, the current tools for this purpose reveal shortcomings with respect to their ease of use and the support offered during CIG acquisition and editing. In this work, we characterise the current landscape of CIG acquisition tools based on the properties of guideline visualisation, organisation, simplicity, automation, manipulation of knowledge elements, and guideline storage and dissemination. Additionally, we describe the CompGuide Editor, a tool for the acquisition of CIGs in the CompGuide model for Clinical Practice Guidelines that also allows the editing of previously encoded guidelines. The Editor guides the users throughout the process of guideline encoding and does not require proficiency in any programming language. The features of the CIG encoding process are revealed through a comparison with already established tools for CIG acquisition.  相似文献   
9.
汽车涂装中产生大量的工业废水,主要包括脱脂废水、磷化废水、电泳废水和喷漆废水等,其典型污染物为重金属离子、表面活性剂、油漆颗粒、磷酸盐等,是一类复杂及难处理的高浓度工业废水。依据废水中所含污染物的不同,对涂装各工序废水进行分质预处理可有效地去除磷酸盐、重金属离子、悬浮固体、油类物质等污染物,有利于减轻后续生物或高级处理单元的负荷,提高整个处理系统的效率。本文综述近年来汽车涂装废水处理方面的研究成果或实践,旨在总结预处理工艺及主体处理工艺的优点及存在的不足,希望为汽车涂装废水处理达标排放及循环回用提供一些借鉴。  相似文献   
10.
针对混凝土坝浇筑块及其仓面表达中非几何信息表达存在的问题,本文首先以施工工艺流程和分部分项工程为基础进行混凝土坝浇筑块的产品结构分解(PBS)和工作结构分解(WBS);建立基于PBS-WBS合成映射的浇筑块特征模型,以基本参数描述浇筑块及其仓面的几何信息,以特征树描述浇筑块及其仓面的非几何信息;最后,采用OWL本体语言表达浇筑块特征,实现浇筑块特征信息的存储、查询及更新等操作。案例分析证明,本方法可以提高对浇筑块及其仓面信息认识的全面性和表达的准确性,帮助施工技术人员合理地分配施工任务和调配施工资源。  相似文献   
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