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1.
Thelwall  Mike  Nevill  Tamara 《Scientometrics》2019,121(3):1793-1801
Scientometrics - The lack of females in many Science Technology, Engineering and Mathematics (STEM) subjects in the USA is an ongoing concern, with many initiatives attempting to redress this...  相似文献   
2.
Food fraud is an intentional act for economic gain. It poses a risk to food integrity, the economy, public health and consumers’ ethics. Seafood is one commodity which has endured extensive fraudulent activity owing to its increasing consumer demand, resource limitations, high value and complex supply chains. It is essential that these fraudulent opportunities are revealed, the risk is evaluated and countermeasures for mitigation are assigned. This can be achieved through mapping of the seafood supply chains and identifying the vulnerability analysis critical control points (VACCP), which can be exposed, infiltrated and exploited for fraudulent activity. This research systematically maps the seafood supply chain for three key commodities: finfish, shellfish and crustaceans in the United Kingdom. Each chain is comprised of multiple stakeholders across numerous countries producing a diverse range of products distributed globally. For each supply chain the prospect of fraud, with reference to species substitution, fishery substitution, illegal, unreported and unregulated substitution, species adulteration, chain of custody abuse, catch method fraud, undeclared product extension, modern day slavery and animal welfare, has been identified and evaluated. This mapping of the fraudulent opportunities within the supply chains provides a foundation to rank known and emerging risks and to develop a proactive mitigation plan which assigns control measures and responsibility where vulnerabilities exist. Further intelligence gathering and management of VACCPs of the seafood supply chains may deter currently unknown or unexposed fraudulent opportunities.  相似文献   
3.
The built environment is a key target of decarbonization policies. However, such policies often have a narrow objective and narrow focus, resulting in ‘policy-resistance’ and unintended consequences. The literature attributes these unintended consequences to a narrow financial focus, adverse incentives, and inadequate handling of knowledge, skills, communication and feedback gaps, but it provides little advice on how these complex interactions can be captured. This paper illustrates the development and application of an integrated approach to address these complex interactions with regard to housing performance, energy, communal spaces and wellbeing. In particular, it explores the dynamics created by these relationships with simulation modelling in participatory settings, and with a diverse group of stakeholders. The simulation results suggest that monitoring is key to improve the performance of the housing stock besides energy efficiency; and investments in communal spaces positively affect the adoption of energy-efficiency measures and the wellbeing of residents. The evaluation results for participatory workshops show this approach was found useful by the stakeholders for supporting more integrated decision-making about housing. In future research, this approach can be implemented for policy problems in specific contexts.  相似文献   
4.
5.
AutoPrep离子色谱法检测饮用水中痕量NO3-和NO2-   总被引:1,自引:0,他引:1  
利用戴安公司全新的AutoPrep自动样品前处理技术,首次提出将OnGuard SPE前处理小柱在线使用的概念,对饮用水中的大部分氯离子进行在线去除的同时,还可对其中的亚硝酸盐和硝酸盐进行快速、准确的定量。该方法选用了自动在线水纯化装置CIRA和OnGuard Ag小柱,运用阀切换技术实现自动进样;适宜的色谱条件为:高容量氢氧化物选择性IonPac AS18阴离子交换色谱柱,淋洗液自动发生装置在线产生KOH进行梯度淋洗,抑制型电导检测;相关方法参数:对于自来水和瓶装水,亚硝酸盐和硝酸盐的检出限(S/N=3)分别为17.8μg/L和25.6μg/L,线性相关系数分别为0.9997和0.9999,RSD〈5%,加标回收率〉92%。该方法具有自动化程度高、操作简单、重现性好、节约时间、成本低廉和对环境友好的特点。此外,研究了前处理小柱的连续使用次数,并对在线和离线的除氯效果进行了比较,认为在线除氯可节约检测成本,且对除氯效果无太大影响。  相似文献   
6.
生态建造:教育套餐和环境手册   总被引:2,自引:0,他引:2  
生态建造是一个关注于传播建成环境中可持续性的需要以及促成可持续性的方式的项目。它针对于两个群体:16-19岁的学生,为他们制作了一个交互式的光盘;建造行业中的专业人员。光盘中提出了这样的问题--你的家和学校有多绿色?它说明了类似于建筑尺度和朝向的设计决策如何影响到建筑在能耗方面的表现和CO2的排放量。光盘包括了衡量如往宅温室节能效果的术语表,来解释它们对建筑的影响。这样学生们就可以对他们自己的学校和家进行评估,并提出怎样的设计可以提高它们的节能效果。如果我们想全球化地实现可持续性的未来,下一代的介入至关重要。环境手册中更深入地研究了这些问题,并关注到了其他建筑类型,如办公建筑。本文描述了正趋于完成的教育光盘和环境手册中涉及的一些根本的环境和教育因素。  相似文献   
7.
Due to the enactment of a stricter drinking water standard for arsenic in the United States, larger quantities of arsenic will be treated resulting in larger volumes of treatment residuals. The current United States Environmental Protection Agency recommendation is to dispose spent adsorbent residuals from arsenic treatment into non-hazardous municipal solid waste (MSW) landfills. The potential of microorganisms to alter the speciation affecting the mobility of arsenic in the disposal environment is therefore a concern. The purpose of this paper was to evaluate the potential of an anaerobic microbial consortium to biologically mobilize arsenate (As(V)) adsorbed onto activated alumina (AA), a common adsorbent used for treating arsenic in drinking water. Three anaerobic columns (0.27 l) packed with 100 g dry weight of AA containing 0.657 mg adsorbed As(V) (expressed as arsenic) per gram dry weight were continuously flushed with synthetic landfill leachate for 257 days. The fully biologically active column was inoculated with methanogenic anaerobic sludge (10 g volatile suspended solids l(-1) column) and was operated with a mixture of volatile fatty acids (VFA) in the feed (2.5 g chemical oxygen demand l(-1) feed). At the end of the experiment, 37% of the arsenic was removed from the column, of which 48% was accounted for by arsenical species identified in the column effluent. The most important form of arsenic eluted was arsenite (As(III)), accounting for nearly all of the identified arsenic in periods of high mobilization. Additionally, two methylated metabolites, methylarsonic acid and dimethylarsinic acid were observed. Mobilization of arsenic is attributed to the biological reduction of As(V) to As(III) since literature data indicates that As(III) is more weakly adsorbed to AA compared to As(V). Batch and continuous assays confirmed that VFA, present in landfill leachates, served as an electron donating substrate supporting enhanced rates of As(V) reduction to As(III). Two control columns, lacking inoculum and/or VFA in the feed displayed low mobilization of arsenic compared to the fully biologically active column. Therefore, leachates generated in MSW landfills could potentially result in the biologically catalyzed mobilization of arsenic from As(V)-laden drinking water residuals.  相似文献   
8.
The study focuses on the role of the fired clay brick making industry (BMI) on deforestation and greenhouse gas (GHG) emissions in Sudan. The BMI is based on numerous kilns that use biomass fuel, mainly wood which is largely harvested unsustainably. This results in potential deforestation and land degradation. Fuelwood consumption data was collected using interviews and questionnaires from 25 BMI enterprises in three administrative regions, namely Khartoum, Kassala and Gezira. Annual fuelwood consumption data (t dm yr− 1) was converted into harvested biomass (m3) using a wood density value of 0.65 t dm m− 3. For annual GHG estimations, the methodological approach outlined by the Intergovernmental Panel on Climate Change (IPCC) was used. According to our results, the annual deforestation associated with the BMI for the whole of Sudan is 508.4 × 103 m3 of wood biomass, including 267.6 × 103 m3 round wood and 240.8 × 103 m3 branches and small trees. Total GHG emissions from the Sudanese BMI are estimated at 378 028 t CO2, 15 554 t CO, 1778 t CH4, 442 t NOX, 288 t NO and 12 t N2O per annum. The combined CO2-equivalent (global warming potential for 100-year time horizon) of the GHG emissions (excluding NOX and NO) is 455 666 t yr− 1. While these emissions form only a small part of Sudan's total GHG emissions, the associated deforestation and land degradation is of concern and effort should be made for greater use of sustainable forest resources and management.  相似文献   
9.
生态景观设计40年   总被引:4,自引:0,他引:4  
本文简要总结了英国生态景观设计的历史,阐述了在景观设计中如何纳入生态设计原则。通过对位于爱丁堡郊区里卡顿的一所新大学校园的规划与建设的案例研究,阐明了生态景观理论在景观设计中的实践。  相似文献   
10.

Objective

Our objective was to compare available techniques reducing artifacts in echo planar imaging (EPI)-based diffusion-weighed magnetic resonance imaging MRI (DWI) of the neck at 3 Tesla caused by B0-field inhomogeneities.

Materials and methods

A cylindrical fat–water phantom was equipped with a Maxwell coil allowing for additional linear B0-field variations in z-direction. The effect of increasing strength of this superimposed gradient on image quality was observed using a standard single-shot EPI-based DWI sequence (sEPI), a zoomed single-shot EPI sequence (zEPI), a readout-segmented EPI sequence (rsEPI), and an sEPI sequence with integrated dynamic shimming (intEPI) on a 3-Tesla system. Additionally, ten volunteers were examined over the neck region using these techniques. Image quality was assessed by two radiologists. Scan durations were recorded.

Results

With increasing strength of the external gradient, marked distortions, signal loss, and failure of fat suppression were observed using sEPI, zEPI, and rsEPI. These artifacts were markedly reduced using intEPI. Significantly better in vivo image quality was also observed using intEPI compared with the other techniques. Scan time of intEPI was similar to sEPI and zEPI and shorter than rsEPI.

Conclusion

The use of integrated 2D shim and frequency adjustment for EPI-based DWI results in a significant improvement in image quality of the head/neck region at 3 Tesla. Combining integrated shimming with rsEPI or zEPI can be expected to provide additional improvements.
  相似文献   
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