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和美乡村视角下的苏南农田“GREEN”水环境治理模式应用研究
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作者 莫宇辰 李永钧 +1 位作者 逯星辉 魏家星 《园林》 2024年第6期51-60,共10页
随着中国宜居宜业和美乡村建设的不断深入,乡村水环境的治理与保护作为乡村生态文明建设的重要组成部分日益受到社会的重视和关注。在以往大规模灰色基础设施建设的背景下,乡村忽略了对于水生态绿色基础设施的构建,生态格局趋于破碎。... 随着中国宜居宜业和美乡村建设的不断深入,乡村水环境的治理与保护作为乡村生态文明建设的重要组成部分日益受到社会的重视和关注。在以往大规模灰色基础设施建设的背景下,乡村忽略了对于水生态绿色基础设施的构建,生态格局趋于破碎。农田空间作为农业面源污染的重要源头,结合多学科视角探索农田水环境污染治理新模式具有高度的必要性。立足于苏南地区独特的农田水网体系,紧密结合农业空间生产属性,研究现有农田水环境治理理论方法与实际建设,提炼以“源头绿色—过程净化—末端吸收—生态保育—循环回用”的苏南农田“GREEN”水环境治理模式,探索风景园林学科水治理方法在农田沟渠、河道及湿地等乡村空间的运用路径,并以常州市中天黄金大农场总体规划为例进行实践应用。推动风景园林学科于乡村生产空间的应用模式探索,为未来农业面源污染防治提供参考借鉴。 展开更多
关键词 和美乡村 乡村水环境 农业面源污染 农田水环境治理 “green”治理模式 常州市中天黄金大农场
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“GREEN”教学模式:构建、实践与反思——新课改下高中课堂教学模式的实践研究
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作者 杨朝霞 张娜 武江娜 《教育实践与研究》 2023年第2期56-60,共5页
为了落实国家对人才培养的各项要求,以及新课程标准对学生学科核心素养的培养要求,河北师范大学附属实验中学的教师们及相关专家经共同研究提出了一种高效绿色的教学模式——“GREEN”教学模式,并对其组成环节、理论依据、教学实践等进... 为了落实国家对人才培养的各项要求,以及新课程标准对学生学科核心素养的培养要求,河北师范大学附属实验中学的教师们及相关专家经共同研究提出了一种高效绿色的教学模式——“GREEN”教学模式,并对其组成环节、理论依据、教学实践等进行了探索,以期为今后的教学发展指明新的方向。 展开更多
关键词 “green”教学模式 高中教学 建构主义理论 深度学习理论
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基于绿色理念的高职英语课堂教学设计与实践--以“Green Living”为例
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作者 王晓 《晋城职业技术学院学报》 2023年第2期43-46,共4页
基于绿色理念,以高职英语课程《新技能英语》第2册Unit5 Green Living为例,从教学设计、实施、创新、反思和改进五个方面进行阐述,旨在让学生树立人与自然和谐共生的环保意识,懂得环境保护要从自身做起,从身边做起,体现人类命运共同体... 基于绿色理念,以高职英语课程《新技能英语》第2册Unit5 Green Living为例,从教学设计、实施、创新、反思和改进五个方面进行阐述,旨在让学生树立人与自然和谐共生的环保意识,懂得环境保护要从自身做起,从身边做起,体现人类命运共同体的价值追求,推动核心素养落地课堂。 展开更多
关键词 绿色 高职英语 课程思政
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“green”的英汉比较研究 被引量:2
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作者 陈晨 曾绪 《西南科技大学学报(哲学社会科学版)》 2010年第2期82-86,共5页
颜色词作为语言词汇的一类,在交际中有着重要的作用,这在英、汉两种语言中都得到体现。由于英、汉两种语言孕育于不同的文化,在发展过程中又制约于各自赖以生存的历史,传统,其同一颜色词的语用差异也就不言而喻。在英、汉语言中,"g... 颜色词作为语言词汇的一类,在交际中有着重要的作用,这在英、汉两种语言中都得到体现。由于英、汉两种语言孕育于不同的文化,在发展过程中又制约于各自赖以生存的历史,传统,其同一颜色词的语用差异也就不言而喻。在英、汉语言中,"green"和"绿"其涵义差异较大。对green在英、汉语言中的语用异同研究发现,文化、历史、传统对词义有着较大的制约和影响。 展开更多
关键词 “green 文化 比较 语用功能
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A Simple and “Green” Method for Synthesis of Magnetic Hollow Silica Spheres and Its <sup>99</sup>Tc<sup>m</sup>Labeled Targeting Studies
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作者 Yicheng Liu Xiazhang Li +4 位作者 Jen Sloppy Yan Huang Pingping Yao Junya Yang Yuxiang Yang 《Open Journal of Inorganic Chemistry》 2017年第1期1-15,共15页
The magnetic hollow silica spheres (MHSS) with uniform cavity size and shell thickness were prepared by a simple and “green” method using functionalized SiO2 spheres as templates. Magnetic particles (Fe3O4) were dep... The magnetic hollow silica spheres (MHSS) with uniform cavity size and shell thickness were prepared by a simple and “green” method using functionalized SiO2 spheres as templates. Magnetic particles (Fe3O4) were deposited on the SiO2 surface by varying the molar ratio of [Fe2+]/[Fe3+] and the molar concentration of iron salts. The obtained magnetic hollow silica spheres exhibited a super-paramagnetic behavior at room temperature. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray powder scattering (XRD) were applied to characterize the MHSS. Besides, their unit cell parameters are calculated according to results indexing to XRD, the MHSS sample prepared at 0.10 M iron salts and 2:1 molar ratio of [Fe2+]/[Fe3+] has a largest cell angle (β) of unit cell. Due to large hollow cavity space and super-paramagnetic characteristics, the inner amino-functionalized MHSS could be labeled with radioisotope 99Tcm to study the MHSS’s magnetic targeting distribution in vivo. These results indicate that the MHSS has potential in the magnetic targeted drug delivery system which reduces the damage to normal cells and improves the therapeutic effect of cancer. 展开更多
关键词 A SIMPLE and “green Method MAGNETIC HOLLOW Silica Spheres MAGNETIC TARGETING Iron Salts RADIOISOTOPE 99Tcm
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从认知角度看“绿色”和“green”的异同 被引量:1
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作者 李蓉 《湖南科技学院学报》 2007年第10期154-155,共2页
"绿色"和"green"作为近年来中外媒体中的流行词而倍受关注。本文从认知的角度探讨"绿色"和"green"的异同:"绿色"和"green"的初始意义、变异的象征意义以及趋同的现代意义。
关键词 绿色 green 异同 认知
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Exploring the “Green” Transformation Planning of Industrial Parks in the Era of Low Carbon Economy
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作者 Caijuan Liang 《World Journal of Engineering and Technology》 2021年第4期747-754,共8页
The core function of <span style="white-space:normal;font-family:;" "="">the </span><span style="white-space:normal;font-family:;" "="">low carbon ec... The core function of <span style="white-space:normal;font-family:;" "="">the </span><span style="white-space:normal;font-family:;" "="">low carbon economy is to change the economic development trend of the whole society. It is necessary to carry out industrial transformation and upgrading according to the concept of sustainable development</span><span style="white-space:normal;font-family:;" "=""> </span><span style="white-space:normal;font-family:;" "="">and to realize integrated technological innovation and efficient economic development without violating the law of ecological and environmental development. In the era of </span><span style="white-space:normal;font-family:;" "="">the </span><span style="white-space:normal;font-family:;" "="">low-carbon economy, industrial parks sho</span><span style="white-space:normal;font-family:;" "="">uld solidly promote the green transformation planning process. Relying on the basic logical framework of green transformation of industrial parks, it can build a green development quality evaluation system of industrial parks and formulate a green planning mechanism and green economic cycle development model in line with the background of </span><span style="white-space:normal;font-family:;" "="">the </span><span style="white-space:normal;font-family:;" "="">low-carbon economy.</span> 展开更多
关键词 Low-Carbon Economy Industrial Park “green Transformation Planning
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“Green Origio生态系统”在农村生活污水处理中的应用 被引量:2
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作者 刘亚琼 贾丽玥 +1 位作者 陈广 何义亮 《净水技术》 CAS 2011年第6期49-52,共4页
农村生活污水分散分布、排水管网不完善,因此所选处理工艺需要符合这一特点。GreenOrigio生态系统处理能力高、占地面积小、维护安装简易,适合处理农村生活污水。结果表明当流速为60~150L/h时,COD去除率维持在87%~93%,出水水... 农村生活污水分散分布、排水管网不完善,因此所选处理工艺需要符合这一特点。GreenOrigio生态系统处理能力高、占地面积小、维护安装简易,适合处理农村生活污水。结果表明当流速为60~150L/h时,COD去除率维持在87%~93%,出水水质可满足城镇污水排放标准一级A标准;当流速为60L/h时,出水TP可满足污水排放标准二级标准。改良的GreenOrigio生态系统中,往TANK2中增添基质填料,当流速为60I/h时使TP去除率从15.76%提高至41.33%~52.52%;TANK2中以梭鱼草为代表,证明GreenOrigio生态系统采用小功率供氧装置,使植物根系得到了较好的生长。通过收割梭鱼草,测量其高度以及统计长高的梭鱼草数量,证明收割有利于植物的生长,进而再次提高水体中营养盐氮磷的去除率。 展开更多
关键词 农村生活污水 green Origio生态系统 填料 收割
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“Green-Ourtopia”的实现路径与现实难题 被引量:1
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作者 翟建宇 赵希 +3 位作者 曹颖 张亚斌 夏晶晶 郑晶茹 《建筑技艺》 2019年第1期82-85,共4页
基于模拟分析的设计成果迭代优化是实现绿色建筑的理想目标的关键路径,结合适应地域气候的绿色建筑分析方法和设计策略,提出绿色建筑理想目标的实现路径。结合台达杯国际太阳能建筑设计竞赛公共建筑类获奖作品,从设计方法学角度分析绿... 基于模拟分析的设计成果迭代优化是实现绿色建筑的理想目标的关键路径,结合适应地域气候的绿色建筑分析方法和设计策略,提出绿色建筑理想目标的实现路径。结合台达杯国际太阳能建筑设计竞赛公共建筑类获奖作品,从设计方法学角度分析绿色建筑设计流程的现状、趋势和挑战,总结当下绿色建筑设计亟待解决的现实难题。 展开更多
关键词 地域气候适应 绿色公共建筑 实现路径
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Strategies for Constructing“Green Heart” in Valley Cities of the Loess Plateau
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作者 LOU Gang TANG Ying 《Journal of Landscape Research》 2018年第1期69-73,82,共6页
Green heart is an important part of urban ecosystem and urban public space. Due to the limitation of geography, hydrology, soil, climate, transportation and other factors, valley cities in the Loess Plateau have certa... Green heart is an important part of urban ecosystem and urban public space. Due to the limitation of geography, hydrology, soil, climate, transportation and other factors, valley cities in the Loess Plateau have certain particularities in the construction of their green hearts. Based on the connotation and characteristics of green heart, a typical valley city of Shenmu in Shaanxi Province was selected for research, and explored the adaptive design strategy of green heart in the city combining with the planning and design of the Central Park in Shenmu, so as to provide a reference point for the construction of green heart in the same type of city. 展开更多
关键词 景观设计 艺术设计 设计方案
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The trust system and ecological civilization:A case study of “green trust”
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作者 WANG Zhen DONG Yu 《Ecological Economy》 2014年第2期159-163,共5页
To promote the ecological civilization has been determined as one of the significant agenda for China's development strategy. However, the shortfall of funding might hinder the progress. Therefore, new financing r... To promote the ecological civilization has been determined as one of the significant agenda for China's development strategy. However, the shortfall of funding might hinder the progress. Therefore, new financing resources and channels are urgently required. Trust has been seen as a popular investing and financing instrument due to its comprehensive benefits such as equity restricting, financial independence and continuity, etc. If trust companies provide services to environmental protection and establish "green trust" or "green funds", it would fully widen financing channel of green industry and contribute to China's sustainable development. 展开更多
关键词 TRUST SYSTEM ECOLOGICAL CIVILIZATION green TRUST
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Extrusion of Thermoplastic Starch: Effect of “Green” and Common Polyethylene on the Hydrophobicity Characteristics
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作者 Muhammad Pervaiz Philip Oakley Mohini Sain 《Materials Sciences and Applications》 2014年第12期845-856,共12页
Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermo... Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermoplastic starch (TPS) is produced from starch processed at high temperatures in the presence of plasticizers, such as water and glycerol. However, because of its hydrophilic nature, TPS exhibits poor mechanical properties when exposed to environmental conditions, such as rain or humidity. The overall objective of this research work was to produce a thermoplastic starch based material with low water absorption that may be used to replace petroleum-based plastics. With a recent emergence of “green” polyethylene (GPE), sourced from renewable feedstock, it has become possible to develop novel biodegradable polymers for various applications. In this work, GPE was melt blended with starch in three different ways;reactive extrusion of GPE and starch facilitated by maleic anhydride (MAH) and dicumyl peroxide (DCP), melt blending of GPE and starch by extrusion, and melt blending of maleated polyethylene and starch by extrusion. Comprehensive testing and analysis has shown that all methods reduced water absorption significantly with some variations across the board. 展开更多
关键词 Biopolymers Thermoplastic STARCH Biodegradable green POLYETHYLENE HYDROPHOBIC Water Absorption Melt-Blending of STARCH RENEWABLE Resources
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Tianxia Qingshi(World Circumstances)in the Political World of Traditional Chinese Scholar Officials:A Case Study of the“Green Sprouts Policy Polemic”in the Early Xining Period of the Northern Song
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作者 Luo Yi'nan 《Social Sciences in China》 2024年第1期89-105,共17页
How to deal with differences is a question that any political body must respond to.The individualist perspective emphasizes that actors will adopt measures to exclude or even eliminate divergent claims in order to gai... How to deal with differences is a question that any political body must respond to.The individualist perspective emphasizes that actors will adopt measures to exclude or even eliminate divergent claims in order to gain control over interests power or statutory policy,but the rich experience of traditional Chinese scholar officials offers the possibility of going beyond the limitations of this perspective.The perspective of“tianxia qingshi(world circumstances)”as a new narrative reveals a unique practical logic and dynamic mechanism in Chinese political civilization that have been overlooked by the individualist perspective.The“Green Sprouts policy(qing miao fa)polemic”in the early years of the New Policies era of the Northern Song dynasty(960-1127)presents a historical situation that has not been given full attention by existing research. 展开更多
关键词 tianxia qingshi(world circumstances) “green Sprouts policy polemic ”dispute practice scholar-official politics
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水禽细小病毒SYBR Green Ⅰ荧光定量PCR检测方法的建立与应用
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作者 汪宏才 商雨 +7 位作者 马瑶 曾哲 张蓉蓉 姚伦 罗玲 李丽 温国元 罗青平 《湖北农业科学》 2024年第6期218-222,共5页
为了建立水禽细小病毒(WPV)快速检测方法,根据序列比对结果在水禽细小病毒NS基因SF3保守区域内设计特异性引物,建立SYBR Green Ⅰ荧光定量PCR通用检测方法。该方法的扩增效率(E)为90.0%,相关系数(R~2)=0.99,标准曲线方程为y=-3.607x+38.... 为了建立水禽细小病毒(WPV)快速检测方法,根据序列比对结果在水禽细小病毒NS基因SF3保守区域内设计特异性引物,建立SYBR Green Ⅰ荧光定量PCR通用检测方法。该方法的扩增效率(E)为90.0%,相关系数(R~2)=0.99,标准曲线方程为y=-3.607x+38.77;除WPV出现S形扩增曲线外,新城疫病毒(NDV)、H9亚型禽流感病毒(H9 AIV)、鸭坦布苏病毒(DTMUV)、鸭肝炎病毒(DHAV)、鸭肠炎病毒(DEV)、鸭呼肠孤病毒(DRV)样品均未出现S形阳性扩增曲线;批内变异系数(CV)为0.15%~0.23%,批间变异系数为0.09%~0.28%。结果表明,SYBR Green Ⅰ荧光定量PCR检测方法重复性好、灵敏度高和特异性强。临床样品检测结果表明,SYBR Green Ⅰ荧光定量PCR与普通PCR的符合率达98.4%,灵敏度是普通PCR的1 000倍。SYBR Green Ⅰ荧光定量PCR检测方法不仅能定性检测WPV,还可以进行定量检测,可用于种鸭场、种鹅场的WPV净化检测,也可用于WPV临床大量样品的快速检测。 展开更多
关键词 水禽细小病毒 检测方法 SYBR green 荧光定量PCR
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约束Green函数与非线性地基梁模态分析 被引量:1
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作者 赵翔 王琦 +1 位作者 朱伟东 李映辉 《动力学与控制学报》 2024年第2期77-84,共8页
在生物和医学领域,微机电系统(MEMS)中的微梁结构在植入人体的使用时,由于体内的细胞环境类似于水凝胶,在这种环境下工作,设备和仪器的精度和稳定性很大程度上受到细胞弹性的影响.为了分析此类地基梁的动力学问题,本文建立了非线性基础... 在生物和医学领域,微机电系统(MEMS)中的微梁结构在植入人体的使用时,由于体内的细胞环境类似于水凝胶,在这种环境下工作,设备和仪器的精度和稳定性很大程度上受到细胞弹性的影响.为了分析此类地基梁的动力学问题,本文建立了非线性基础上的梁振动模型,研究了任意位置弹簧和非线性弹簧基础上的梁模态.通过Laplace变换和线性叠加原理,得到了一种约束Green函数,利用数值计算验证方案的有效性,并研究了各种重要物理参数的影响,发现弹簧位置向跨中移动时,模态对称性被打破,弹簧刚度增加,模态阶数改变. 展开更多
关键词 约束green函数 LAPLACE变换 非线性弹簧基础 模态分析 叠加原理
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猪流行性腹泻病毒SYBR Green I实时荧光定量PCR检测方法的建立
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作者 董苏洁 孔宁 +9 位作者 秦文珍 翟焕杰 翟雪滢 杨心雨 童武 郑浩 于海 童光志 李有文 单同领 《中国动物传染病学报》 CAS 北大核心 2024年第2期174-180,共7页
为了建立高效、灵敏的猪流行性腹泻病毒(PEDV)检测方法,本研究从GenBank数据库中获取PEDV N基因序列,扩增出PEDV N基因标准质粒,并在N基因的保守区域内设计了一对特异性荧光定量引物,成功建立了SYBR Green I实时荧光定量PCR检测方法。... 为了建立高效、灵敏的猪流行性腹泻病毒(PEDV)检测方法,本研究从GenBank数据库中获取PEDV N基因序列,扩增出PEDV N基因标准质粒,并在N基因的保守区域内设计了一对特异性荧光定量引物,成功建立了SYBR Green I实时荧光定量PCR检测方法。经过一系列试验表明,该检测方法线性关系良好,R^(2)值为0.99;特异性强,敏感性高,最低可检测至2.23 copies/μL,比普通PCR灵敏约100倍;重复性好,组内变异系数为0.25%~0.43%,组间变异系数为0.67%~0.97%;对于各地区96份临床样品检测出PEDV阳性率为25%。本研究建立的实时荧光定量PCR检测方法为PEDV的临床诊断、流行病学调查以及定量研究提供了有效的检测工具。 展开更多
关键词 猪流行性腹泻病毒 N基因 SYBR green I 荧光定量PCR
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多层非均质边坡降雨入渗分析的改进Green-Ampt模型
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作者 蒋水华 刘贤 +1 位作者 黄劲松 周创兵 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第6期1177-1186,共10页
边坡降雨入渗分析对于降雨型滑坡加固设计、治理和风险防控至关重要。经典的Green-Ampt模型参数虽然具有明确的物理意义,计算便捷,但是忽略了入渗区客观存在的过渡层,并且不能有效分析考虑土体渗透系数空间变异性的多层非均质边坡降雨... 边坡降雨入渗分析对于降雨型滑坡加固设计、治理和风险防控至关重要。经典的Green-Ampt模型参数虽然具有明确的物理意义,计算便捷,但是忽略了入渗区客观存在的过渡层,并且不能有效分析考虑土体渗透系数空间变异性的多层非均质边坡降雨入渗问题。为此,提出了一种适用于多层非均质边坡降雨入渗分析的改进Green-Ampt模型,考虑了降雨入渗的椭圆形过渡层,推导了不同降雨历时下边坡含水率分布情况。同时,以无限长边坡模型为例,通过4种常见的边坡工况验证了该模型的有效性,并进行了降雨入渗条件下非均质边坡稳定性分析。结果表明:对于设定的4种工况,提出的改进Green-Ampt模型计算的边坡体积含水量分布、安全系数和滑动面深度与Richards方程数值解吻合,而基于修正Green-Ampt模型计算的边坡体积含水量和滑动面分布存在偏差,边坡安全系数偏小。此外,基于提出的改进Green-Ampt模型能够准确识别最危险滑动面位置。研究成果可为多层非均质边坡降雨入渗分析及降雨型滑坡加固设计及风险防控提供理论参考。 展开更多
关键词 非均质边坡 降雨入渗 稳定性分析 改进green-Ampt模型 空间变异性
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Green Synthesis of Silver Nanoparticles Using Aqueous Orange and Lemon Peel Extract and Evaluation of Their Antimicrobial Properties
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作者 Amra Bratovcic Amna Dautovic 《Advances in Nanoparticles》 CAS 2024年第2期11-28,共18页
Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the ve... Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the versatility of biomedical applications of metal nanoparticles. In this paper, AgNPs were synthetized at different reaction parameters such as the type and concentration of the extracts, metal salt concentration, temperature, speed stirring, and pH. The antibacterial properties of the obtained silver nanoparticles against E. coli, as well as the physical and chemical characteristics of the synthesized silver nanoparticles, were investigated. UV-Vis spectroscopy was used to confirm the formation of AgNPs. In addition to green biogenic synthesis, chemical synthesis of silver nanoparticles was also carried out. The optimal temperature for extraction was 65˚C, while for the synthesis of AgNPs was 35˚C. The synthesis is carried out in an acidic environment (pH = 4.7 orange and pH = 3.8 lemon), neutral (pH = 7) and alkaline (pH = 10), then for different concentrations of silver nitrate solution (0.5 mM - 1 mM), optimal time duration of the reaction was 60 min and optimal stirring speed rotation was 250 rpm on the magnetic stirrer. The physical properties of the synthesized silver nanoparticles (conductivity, density and refractive index) were also studied, and the passage of laser light through the obtained solution and distilled water was compared. Positive inhibitory effect on the growth of new Escherichia coli colonies have shown AgNPs synthesized at a basic pH value and at a 0.1 mM AgNO<sub>3</sub> using orange or lemon peel extract, while for a 0.5 mM AgNO<sub>3 </sub>using lemon peel extract. 展开更多
关键词 green Synthesis Silver Nanoparticles Orange and Lemon Peel Extract Antibacterial Activity Escherichia coli
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Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System
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作者 Clark B. Neely Francis M. Rouquette Jr. +3 位作者 Cristine L.S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith 《Agricultural Sciences》 2024年第3期333-357,共25页
Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their... Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha<sup>-1</sup>) and contributed the most total N (167 kg∙ha<sup>-1</sup>) and total C (3043 kg∙ha<sup>-1</sup>) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea produced 8.41 t DM ha<sup>-1</sup> with a total N yield of 319 kg N ha<sup>-1</sup> and total C production of 3835 kg C ha<sup>-1</sup>. The WSL treatments had only small effects on rye forage yield and N concentration, possibly due to mineralization of N from a large SOC pool already in place. The CSL treatments also had only minimal effects on sorghum-sudangrass forage production. Winter pea, arrow leaf and crimson clover were productive cool season legumes and could be useful as green manure crops. Mungbean and cowpea (Vigna unguiculata [L.] Walp.) were highly productive warm season legumes but may include more production risk in green manure systems due to soil moisture competition. 展开更多
关键词 Annual Legumes Soil N Soil Organic C green Manure Deer Browse Forage Cropping Systems
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Green Hydrogen: Perspectives and Challenges in Using the Natural Gas Network in Ceará/Brazil
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作者 Francisco Alfredo de Castro Mona Lisa Moura de Oliveira +1 位作者 Lutero Carmo de Lima Daniel Silveira Serra 《Journal of Geoscience and Environment Protection》 2024年第3期70-94,共25页
Climate change, mainly caused by the use of non-renewable fuels, has raised global concerns and led to the search for less polluting energy sources, making hydrogen a promising energy alternative with the potential to... Climate change, mainly caused by the use of non-renewable fuels, has raised global concerns and led to the search for less polluting energy sources, making hydrogen a promising energy alternative with the potential to contribute to changes in the energy mix of various countries through the use of technologies that enable its production and use with low or zero carbon emissions. In this context, Brazil has aroused great interest from other countries in exploring its renewable resources for the production of hydrogen (green hydrogen). In this sense, the use of natural gas pipelines and the use of hydrogen in mixtures with natural gas have become the subject of studies due to their economically viable alternative for the immediate use of this energy vector. However, there are still technical and regulatory challenges regarding the integration of hydrogen into the existing natural gas pipeline network. In this context, the present study aims to address the effects of hydrogen interaction with the structure of natural gas pipeline steel and the regulatory barriers to the use of this network for the transportation of green hydrogen, particularly in the state of Ceará/Brazil. After extensive analysis of literature and regulatory documents, it was concluded that: 1) Ceará/Brazil has strong potential to meet the demand for green hydrogen through the use of solar and wind energy sources;2) there is feasibility for the adaptation or conversion of natural gas infrastructure for the transportation of green hydrogen;3) discussions regarding the regulatory competence of green hydrogen transportation and distribution through the natural gas network in Brazil are still incipient;4) the current regulation of the natural gas industry can serve as a subsidy for the regulation of green hydrogen and natural gas transportation. 展开更多
关键词 Decarbonization Natural Gas green Hydrogen Pipelines
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