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1.
The rise in the number of fungi that resisted antifungal action is of serious concern nowadays. In this study, the potential of acid condensate (AC) produced from microwave-assisted pyrolysis of palm kernel shell (PKS) was investigated for its antifungal properties through molecular docking evaluation. The phenolic-rich AC was determined for its chemical compositions using the GC–MS analysis where compounds with the highest phenolics content were further evaluated (using the Autodock Tools 1.5.7) for its potential enzymes/protein binding properties. From the GC–MS analysis, catechol, guaiacol and syringol were present at highest percentages. This directly correlates with results obtained from the molecular docking works where all these ligands managed to bind (indicated by H-bond, π-stacking, hydrophobic interaction) with some of the amino acid at the active sites which indicate its potential to inhibit substrate binding of this enzyme. As a conclusion, this study demonstrated the potential use of AC from agricultural biomass such as PKS as a natural-based antifungal agent that can reduce environmental and health impacts.  相似文献   
2.
储罐配管在温差作用下产生热位移会导致管壁产生热应力,未采用柔性连接的配管由于热应力集中作用可能发生破漏。针对与石油化工储罐非柔性连接的配管的安全问题,应用ANSYS有限元分析软件模拟计算石化企业典型配管的热应力分布;根据不同类型配管的分析结果,提出了工程技术与管理方面的针对性安全措施。研究结果表明:温差效应对石化储罐配管热应力影响显著,随内外温差的增加,配管应力集中的区域增大,最大热应力值增大;补偿措施能够改善配管的柔性,降低配管应力;约束载荷限制配管热膨胀从而增大配管应力;三通管是多根配管接合的区域,这种复杂管道交汇处会形成明显应力集中。研究结果对于提高石油化工非柔性连接配管安全性有一定的指导意义。  相似文献   
3.
水生态环境质量评价体系研究   总被引:4,自引:1,他引:3  
流域水生态环境质量评价体系是为流域环境管理提供基础数据,协助管理者开展流域保护措施的重要技术支持。该文深入剖析了发达国家典型水生态环境质量评价体系,归纳分析了其体系框架、构成特点、方法适用性和借鉴意义。结合前期研究基础,对评价体系的技术内容进行了完善和补充,明确了参照点位的选择原则,补充了评价方法选择的技术路线,提出了增设和实施不同监测计划的方案,最终提出生态环境质量评价技术体系框架。  相似文献   
4.
Environmental Science and Pollution Research - The estuarine delta of the Yellow River is a region of strong land-ocean-human interactions that undergoes a unique evolutionary process. The delta is...  相似文献   
5.
Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
6.
• Published data was used to analyze the fate of ARGs in water treatment. • Biomass removal leads to the reduction in absolute abundance of ARGs. • Mechanism that filter biofilm maintain ARB/ARGs was summarized. • Potential BAR risks caused by biofiltration and chlorination were proposed. The bacterial antibiotic resistome (BAR) is one of the most serious contemporary medical challenges. The BAR problem in drinking water is receiving growing attention. In this study, we focused on the distribution, changes, and health risks of the BAR throughout the drinking water treatment system. We extracted the antibiotic resistance gene (ARG) data from recent publications and analyzed ARG profiles based on diversity, absolute abundance, and relative abundance. The absolute abundance of ARG was found to decrease with water treatment processes and was positively correlated with the abundance of 16S rRNA (r2 = 0.963, p<0.001), indicating that the reduction of ARG concentration was accompanied by decreasing biomass. Among treatment processes, biofiltration and chlorination were discovered to play important roles in shaping the bacterial antibiotic resistome. Chlorination exhibited positive effects in controlling the diversity of ARG, while biofiltration, especially granular activated carbon filtration, increased the diversity of ARG. Both biofiltration and chlorination altered the structure of the resistome by affecting relative ARG abundance. In addition, we analyzed the mechanism behind the impact of biofiltration and chlorination on the bacterial antibiotic resistome. By intercepting influent ARG-carrying bacteria, biofilters can enrich various ARGs and maintain ARGs in biofilm. Chlorination further selects bacteria co-resistant to chlorine and antibiotics. Finally, we proposed the BAR health risks caused by biofiltration and chlorination in water treatment. To reduce potential BAR risk in drinking water, membrane filtration technology and water boiling are recommended at the point of use.  相似文献   
7.
旅游产业生产效率是衡量旅游资源合理利用与旅游经济发展水平的重要依据。基于DEA Malmquist指数二次分解模型,对2000~2015年江苏13个地市旅游产业效率的时空演变特征及影响因素进行探究。结果显示:(1)2000~2015年全省旅游全要素生产率总体上有所上升,但上升幅度不大,年平均值为1020;空间分布上,旅游全要素生产率水平呈现明显的地区差异性, 南部城市普遍高于北部城市,东部城市优于西部城市。(2)各地市旅游全要素生产率增长主要归功于技术进步变化,其中,规模技术进步变化是影响各地市旅游全要素变化的最主要因素,纯技术进步变化次之,纯技术效率变化和规模效率变化对旅游全要素的影响最小。(3)面板回归结果表明,产业结构、对外开放水平、经济发展程度、交通、劳动力是各地市旅游产业生产效率变动的主要影响因素。因此,不同地区应采取不同的旅游发展政策,推进旅游产业技术进步,大力提升旅游产业生产效率。 关键词: DEA Malmquist指数;二次分解;旅游产业效率;江苏省  相似文献   
8.
针对现有技术下由于微网中不可控微源出力预测和负荷预测均存在误差较大而引起微网优化调度结果不准确的问题,提出在传统微网经济调度模型中增加不确定性描述模型,得到不同侧重点下的微网经济优化结果,并对结果进行分析。首先,通过利用区间数描述预测不确定性,并结合隶属度函数推导容忍度概念。其次,在并网运行模式的微网结构上建立以运行成本最低为目标函数的微网优化调度模型,并将该模型转换为区间数形式表示。最后,利用粒子群优化算法并以MATLAB为主要工具对上述模型进行求解,得到微网24 h出力优化区间解结果,并对结果进行详细分析。算例通过对某并网型微网进行分析,验证了所提模型的科学性和有效性。  相似文献   
9.
When accounting the CO2 emissions responsibility of the electricity sector at the provincial level in China,it is of great significance to consider the scope of both producers’ and the consumers’ responsibility,since this will promote fairness in defining emission responsibility and enhance cooperation in emission reduction among provinces.This paper proposes a new method for calculating carbon emissions from the power sector at the provincial level based on the shared responsibility principle and taking into account interregional power exchange.This method can not only be used to account the emission responsibility shared by both the electricity production side and the consumption side,but it is also applicable for calculating the corresponding emission responsibility undertaken by those provinces with net electricity outflow and inflow.This method has been used to account for the carbon emissions responsibilities of the power sector at the provincial level in China since 2011.The empirical results indicate that compared with the production-based accounting method,the carbon emissions of major power-generation provinces in China calculated by the shared responsibility accounting method are reduced by at least 10%,but those of other power-consumption provinces are increased by 20% or more.Secondly,based on the principle of shared responsibility accounting,Inner Mongolia has the highest carbon emissions from the power sector while Hainan has the lowest.Thirdly,four provinces,including Inner Mongolia,Shanxi,Hubei and Anhui,have the highest carbon emissions from net electricity outflow- 14 million t in 2011,accounting for 74.42% of total carbon emissions from net electricity outflow in China.Six provinces,including Hebei,Beijing,Guangdong,Liaoning,Shandong,and Jiangsu,have the highest carbon emissions from net electricity inflow- 11 million t in 2011,accounting for 71.44% of total carbon emissions from net electricity inflow in China.Lastly,this paper has estimated the emission factors of electricity consumption at the provincial level,which can avoid repeated calculations when accounting the emission responsibility of power consumption terminals(e.g.construction,automobile manufacturing and other industries).In addition,these emission factors can also be used to account the emission responsibilities of provincial power grids.  相似文献   
10.
采用正弦波变化振荡的辐射热流,对热厚PMMA(聚甲基丙烯酸甲酯)的热解和着火过程进行研究,同时采用数值模拟,对实验结果进行验证和补充。结果表明,表面温度和深度温度随着时间而增加,温度由于周期性的辐射而发生振荡,而振荡幅度随着深度的增加而衰减;表面温度与深度温度振荡存在时间延迟;着火时间随着热流振荡周期的增大而减小,主要由于平均热流密度随着周期增大而增大。  相似文献   
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