organic

有机
  • 文章类型: Journal Article
    发光共价有机骨架(COF)是一类有前途的晶体材料,已证明可用于传感和发光二极管。然而,单一COF发出的白光尚未实现,因为它需要同时发出蓝色的多组分有机发色团,绿色,和红灯。在这项工作中,我们报道了在其核心结构上掺入不同官能团后,利用2,1,3-苯并噻二唑的可调发射性能,成功合成了具有有效白光发射的单一COF,这导致三个配体的形成,即,4\',4-(苯并噻二唑-4,7-二基)-二苯甲醛(BTD),4,4'-(苯并硒二唑-4,7-二基)-二苯甲醛(BSD),和4,4'-(萘并[2,3-c][1,2,3]硒二唑-4,9-二基)-二苯甲醛(NSD),发出蓝色,绿色,和可见光谱的红色区域。我们表明,只有当BTD,BSD,和NSD由于从BTD到BSD/NSD的促进的能量转移过程而组装在单个COF结构中。这项工作展示了一种独特的方法来开发基于COF结构的新型白色发光材料。
    Emissive covalent organic frameworks (COFs) are a promising class of crystalline materials that have demonstrated applications for sensing and light-emitting diodes. However, white light emission from a single COF has not been achieved yet as it requires multicomponent organic chromophores that simultaneously emit blue, green, and red light. In this work, we report the successful synthesis of a single COF with efficient white light emission by utilizing tunable emission properties of 2,1,3-benzothiadazole after incorporating different functional groups on its core structure, which results in the formation of three ligands, i.e., 4\',4-(benzothiadiazole-4,7-diyl)-dibenzaldehyde (BTD), 4,4\'-(benzoselenadiazole-4,7-diyl)-dibenzaldehyde (BSD), and 4,4\'-(naphtho[2,3-c][1,2,3] selenadiazole-4,9-diyl)-dibenzaldehyde (NSD), that emit in the blue, green, and red regions of the visible light spectrum. We show that white light emission can only occur when BTD, BSD, and NSD are assembled in a single COF structure due to the facilitated energy transfer process from BTD to BSD/NSD. This work demonstrates a unique approach to developing new white light-emitting materials based on the COF structure.
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  • 文章类型: Journal Article
    由于内在的权衡,优化小农农场的可持续性带来了挑战。在加纳的有机和传统可可小农农业研究中,使用联合国粮食及农业组织(FAO)粮食和农业系统可持续评估(SAFA)指南和可持续性监测和评估常规(SMART)-农场工具对398个农场进行评估。有机农业在环境方面表现出协同作用(例如,土壤质量,能源效率)以及生物多样性保护和风险管理之间的关系。传统农业显示出潜在的脆弱性,包括与长期投资的权衡(例如,化学输入)和物种多样性。这两个系统都需要为短期经济和环境可持续性量身定制的方法,与整个社区的长期目标保持一致。为了减少传统农业的取舍,小农应该采用材料再利用等做法,回收,并在他们的业务中恢复。
    Optimizing sustainability among smallholder farms poses challenges due to inherent trade-offs. In the study of organic and conventional cocoa smallholder farming in Ghana, 398 farms are assessed using the Food and Agriculture Organsation of the United Nations (FAO) Sustainability Assessment of Food and Agriculture systems (SAFA) Guidelines and Sustainability Monitoring and Assessment Routine (SMART)-Farm Tool. Organic farming exhibited synergies in environmental aspects (e.g., soil quality, energy efficiency) and between biodiversity conservation and risk management. Conventional farming showed potential vulnerabilities, including trade-offs with long-range investments (e.g., chemical inputs) and species diversity. Both systems demand tailored approaches for short-term economic and environmental sustainability, aligning with community-wide long-term goals. To mitigate trade-offs in conventional farming, smallholders should adopt practices like material reuse, recycling, and recovery within their operations.
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  • 文章类型: Journal Article
    背景:在过去的十年中,有机食品(OF)的生产和消费受到越来越多的关注。科学研究表明,就营养素和农药含量而言,有机水果和蔬菜(FV)的质量更高,但与传统食品(CF)相比,这些产品是否有潜在更大的健康益处似乎很难得出结论。
    目的:确定当前的科学文献是否表明富含有机FV的饮食比常规产品的饮食更健康。
    方法:使用PubMed和WebofScience数据库对2003年1月至2022年12月之间发表的文章进行了系统搜索。文章由2名审稿人统一分析,使用特定的模板汇总表,得分从1到5。使用Jadad评分和法国国家卫生管理局方法评估了人类的证据水平和研究质量。
    结果:共纳入12项人体研究。研究经常报告矛盾甚至相反的结果,有方法论上的局限性。12项研究中只有6项发现OF与评估的健康结果之间存在显着关联。
    结论:目前的数据无法得出关于与传统农业相比,有机种植的产品富含FV的饮食具有更大的健康益处的确切结论。研究设计中缺乏可用数据和相当大的异质性(参与者,暴露,持续时间,健康结果,和残余混杂因素)。需要精心设计的介入研究。
    BACKGROUND: Over the past decade, the production and consumption of organic food (OF) have received increasing interest. Scientific studies have shown better quality of organic fruit and vegetables (FV) in terms of nutrients and pesticide contents, but it appears difficult to conclude if there are potentially greater health benefits of these products compared with conventional food (CF).
    OBJECTIVE: To determine whether the current scientific literature demonstrates that a diet rich in organic FV is healthier than 1 based on conventional produce.
    METHODS: A systematic search was conducted using the PubMed and Web of Science databases for articles published between January 2003 and December 2022. Articles were analyzed uniformly by 2 reviewer, using a specific template summary sheet, and scored from 1 to 5. The level of evidence and the quality of studies in humans were assessed using the Jadad score and the French National Authority for Health method.
    RESULTS: A total of 12 human studies were included. Studies often reported contradictory or even opposite results, with methodological limitations. Only 6 of the 12 studies found significant associations between OF and the health outcomes evaluated.
    CONCLUSIONS: The current data do not enable a firm conclusion about a greater health benefit for a diet rich in FV based on products grown organically compared with conventional farming. There is a paucity of available data and considerable heterogeneity in study designs (participants, exposures, durations, health outcomes, and residual confounding factors). Well-designed interventional studies are required.
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  • 文章类型: Journal Article
    碘对甲状腺激素的产生至关重要。牛奶和乳制品是许多国家碘的重要来源。我们旨在系统地回顾各国之间牛奶碘浓度的变化,季节和耕作实践。自2006年以来,我们搜索了在线食品成分表和已发表的文献以获取数据。34个国家(来自66个来源)的牛奶碘浓度范围为5.5至49.9μg/100g(中位数为17.3μg/100g)。荟萃分析确定:(i)冬季牛奶的碘浓度明显高于夏季牛奶(平均差5.97μg/100g;p=0.001),和(ii)常规比有机牛奶(平均差6.00μg/100g;p<0.0001)。亚组分析表明,有机牛奶和常规牛奶之间的差异仅在夏季显着(p=0.0003)。牛奶碘浓度的季节性变化可能会影响碘的摄入量和状态,因此在饮食调查中应予以考虑。以及在评估人口碘状况时。
    Iodine is essential for thyroid hormone production. Milk and dairy products are important sources of iodine in many countries. We aimed to review systematically the variation in milk‑iodine concentration between countries, seasons and farming practice. We searched online food composition tables and published literature for data since 2006. Milk‑iodine concentration was available for 34 countries (from 66 sources) and ranged from 5.5 to 49.9 μg/100 g (median 17.3 μg/100 g). Meta-analyses identified that iodine concentration is significantly higher in: (i) winter than summer milk (mean difference 5.97 μg/100 g; p = 0.001), and (ii) in conventional than in organic milk (mean difference 6.00 μg/100 g; p < 0.0001). Sub-group analysis showed that the difference between organic and conventional milk was only significant in summer (p = 0.0003). The seasonal variation in milk‑iodine concentration may affect iodine intake and status so should be considered in dietary surveys, and when assessing population iodine status.
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  • 文章类型: Journal Article
    鼠尾草(SalviaofficinalisL.)是一种药用和芳香植物(MAP),属于唇形科。它的形态,生产和化学特性受到非生物和生物因素的影响。使用生物刺激剂似乎是最有趣的创新做法之一,因为它们可以代表实现可持续和有机农业的有希望的方法。尽管在园艺中应用广泛,生物刺激剂对MAPs的使用研究甚少。在此基础上,在为期2年的研究中进行了一项田间试验,以评估使用不同类型的生物刺激剂(含有海藻,富里酸和蛋白质水解产物)和两个在形态学上的应用频率,生产,以及在地中海环境中有机生长的刺槐的化学特性。形态学,生产,和化学参数受因素的影响。生物刺激剂的应用产生了更高的植物高度,叶绿素含量,相对含水量,与对照植物相比,生物量产量和精油产量。此外,更频繁的生物刺激剂的应用产生更高的生物量和精油产量。每周施用富里酸和蛋白质水解产物可产生最高的总新鲜产量(在3.9至8.7tha-1之间)和总干产量(在1.3至2.5tha-1之间)。精油产量几乎翻了一番(33.9kgha-1),蛋白质水解物的应用频率更高。在这项研究中,确定了44种精油化合物,频率因素对38个化合物的百分比有显著影响。一些最具代表性的单萜的百分比最高,如1,8-桉树脑,α-thujone和樟脑,在生物刺激的植物中观察到,与对照植物相比,平均增加6%至35%。总酚的最高值,迷迭香酸,在对照植物中获得了抗氧化活性,并且使用生物刺激剂的频率较低。这项研究强调了在农业有机系统中生产时,如何使用生物刺激剂来改善鼠尾草的生产性能和精油参数。同时,生物刺激剂的应用导致总酚类物质的减少,抗氧化活性和迷迭香酸值。
    Sage (Salvia officinalis L.) is a medicinal and aromatic plant (MAP) belonging to the Lamiaceae family. Its morphological, productive and chemical characteristics are affected by abiotic and biotic factors. The use of biostimulants seems to be one of the most interesting innovative practices due to fact they can represent a promising approach for achieving sustainable and organic agriculture. Despite a large application in horticulture, the use of biostimulants on MAPs has been poorly investigated. On this basis, a field experiment in a 2-year study was done to assess the effect of foliar treatments with different types of biostimulants (containing seaweeds, fulvic acids and protein hydrolysates) and two frequencies of application on morphological, productive, and chemical characteristics of S. officinalis grown organically in Mediterranean environment. Morphological, productive, and chemical parameters were affected by the factors. The biostimulant application generated higher plant height, chlorophyll content, relative water content, biomass yield and essential oil yield compared to control plants. In addition, more frequent application of biostimulants produced higher biomass and essential oil yield. The application of fulvic acid and protein hydrolysates every week produced the highest total fresh yields (between 3.9 and 8.7 t ha-1) and total dry yields (between 1.3 and 2.5 t ha-1). The essential oil yield almost doubled (33.9 kg ha-1) with a higher frequency of protein hydrolysates application. In this study, 44 essential oil compounds were identified, and the frequency factor significantly influenced the percentage of 38 compounds. The highest percentage of some of the most representative monoterpenes, such as 1,8-cineole, α-thujone and camphor, were observed in biostimulated plants, with average increases between 6% and 35% compared to control plants. The highest values for total phenolics, rosmarinic acid, antioxidant activity were obtained in control plants and with a lower frequency of biostimulant applications. This study emphasizes how biostimulant applications may be used to improve sage production performance and essential oil parameters when produced in agricultural organic system. At the same time, biostimulants application caused a decrease in total phenolic, antioxidant activity and rosmarinic acid values.
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  • 文章类型: Journal Article
    有机半导体功率器件因其柔性等优点而受到越来越多的关注,低制造成本,和可持续性。它们在诸如柔性电子器件和生物医学器件的领域中发现了广泛的应用。然而,在电力应用领域,缺乏可靠的有机半导体功率器件主要归因于有机材料有限的热稳定性和电稳定性。本文从器件结构、有机材料,和制造方法。明确了未来的发展目标是通过更高性能的结构设计来增强有机晶体管的耐电压性和热稳定性,流动性较高的材料,和更高质量的制造方法。结构的不断创新和发展,材料,这些设备的制造将产生更多的新颖设备,为有机半导体功率器件的应用提供了更多的可能性。这些信息对相关领域的工程师具有重要的参考价值和指导意义。
    Organic semiconductor power devices have been attracting increasing attention due to their advantages such as flexibility, low fabrication cost, and sustainability. They have found wide applications in fields such as flexible electronic devices and biomedical devices. However, in the field of power applications, the lack of reliable organic semiconductor power devices is mainly attributed to the limited thermal stability and electrical stability of organic materials. This article provides a detailed review of the development status of organic semiconductor power devices from three aspects: device structure, organic materials, and fabrication methods. It clarifies that the future development goal is to enhance the voltage resistance and thermal stability of organic transistors through higher-performance structure design, higher-mobility materials, and higher-quality fabrication methods. The continuous innovation and development of the structures, materials, and fabrication of these devices will generate more novel devices, offering more possibilities for the application of organic semiconductor power devices. This information is of great reference value and guidance significance for engineers in related fields.
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  • 文章类型: Journal Article
    标题化合物,C19H30O2Si,在100K时具有三斜晶系(P)对称性。环氧基团的O原子具有伪轴取向,环己基和苯环之间的二面角为85.80(8)°。C-O-Si-Ct(t=叔丁基)扭转角为-177.40(14)°。在水晶里,成对的C-H∞O连接将摩尔分子连接到具有R22(8)环的反转二聚体中。
    The title compound, C19H30O2Si, has triclinic (P) symmetry at 100 K. The O atom of the epoxide group has a pseudoaxial orientation and the dihedral angle between the cyclo-hexyl and benzene rings is 85.80 (8)°. The C-O-Si-C t (t = tert-but-yl) torsion angle is -177.40 (14)°. In the crystal, pairwise C-H⋯O links connect the mol-ecules into inversion dimers featuring R 2 2(8) loops.
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  • 文章类型: Journal Article
    提高养分利用效率和减少温室气体(GHG)排放是有机认证乳制品运营的重要环境优先事项。这项研究的目的是量化纽约6个有机奶牛场的年度养分使用量和温室气体排放量。使用CornellNMB计算器估算了农场门养分质量平衡(NMB)。使用CoolFarmTool(CFT)和COMET估算了整个农场的温室气体排放量。农场大门的NMB很低,N1的-6.5至19kgNha-1(无豆类N固定),26至71kgNha-1,用于N2(包括氮固定),-2.4至8.2千克Pha-1用于P,和1.1至19.8千克Kha-1K。额外的营养素进口,再加上营养管理规划,充足的豆科植物和饮食平衡可能有助于改善P平衡,并确保系统中没有N个缺陷。CFT估计的年度温室气体排放强度为每公斤脂肪和蛋白质校正牛奶(FPCM)0.98至2.10kgCO2-eq,从0.69到2.48kgCO2-eqkgFPCM-1,由COMET估计。肠道发酵,饲料生产、燃料和能源使用是温室气体的最大来源。对于有液体粪肥储存的农场,粪肥管理也是一个重要来源。CFT对土壤碳(C)储量变化的估计与以前的研究一致或较小,和COMET的估计意见一致或更高。土壤碳储量变化结果的变异性和不确定性表明需要更多的研究和新的方案。个别管理变更对温室气体排放强度的影响较小,CFT的-8%到+7%,和-8%到+8%的彗星。导致温室气体排放强度最大降低的管理变化包括提高个体奶牛的生产率和牛奶与总饲料的比率,和实施粪肥处理系统。
    Improving nutrient use efficiency and reducing greenhouse gas (GHG) emissions are important environmental priorities for organic-certified dairy operations. The objectives of this research were to quantify annual nutrient use and GHG emissions in 6 organic New York dairy farms. Farm-gate nutrient mass balances (NMB) were estimated with the Cornell NMB calculator. Whole-farm GHG emissions were estimated using Cool Farm Tool (CFT) and COMET. Farm-gate NMBs were low, ranging from -6.5 to 19 kg N ha-1 for N1 (without legume N fixation), 26 to 71 kg N ha-1 for N2 (including N fixation), -2.4 to 8.2 kg P ha-1 for P, and 1.1 to 19.8 kg K ha-1 for K. Additional nutrient imports, coupled with nutrient management planning, adequate legume stands and diet balancing may help improve P balances, and ensure no N deficiencies in the system. Estimates of annual GHG emission intensity ranged from 0.98 to 2.10 kg CO2-eq per kg of fat and protein corrected milk (FPCM) estimated by CFT, and from 0.69 to 2.48 kg CO2-eq kg FPCM-1 estimated by COMET. Enteric fermentation, feed production and fuel and energy use represented the largest sources of GHGs. For farms with liquid manure storages, manure management was also a significant source. Estimates of soil carbon (C) stock changes from CFT were in agreement or smaller than previous studies, and estimates from COMET were in agreement or greater. Variability and uncertainty in the results for soil C stock change indicate more research and new protocols are needed. Impact of individual management changes on GHG emissions intensity were small, ranging from -8 to +7% in CFT, and -8% to +8% in COMET. The management changes that resulted in the largest reductions in GHG emissions intensity included increasing individual cow productivity and milk to total feed ratio, and implementation of manure treatment systems.
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  • 文章类型: Journal Article
    为了克服由超薄自组装活性层的光吸收不足和ALD生长的低泄漏电流传输层的高成本使用引起的严重问题,我们成功开发了一种低成本的,浮膜转移和多层层压(FFTML)的简单而简便的策略,用于构建高效的无ALD宽带偏振敏感有机光电探测器(OPD),具有供体/受体平面异质结(PHJ)和供体的两种常用结构:受体多层体异质结(BHJ)。发现FFTML的基于PHJ的偏振敏感OPD由于高载流子注入势垒而具有低暗电流,说明它更适合应用于低偏振光检测场景。相比之下,由于更多的光激子转移到供体:受体界面并解离成光激发载体,因此FFTML基于BHJ的器件在整个波长上具有更高的光谱响应度。此外,薄膜厚度,通过增加BHJ层的层压数量来调整,对偏振敏感的光电检测性能有很大的影响。FFTML的偏振敏感4-BHJOPD最终实现了8.33×1010琼斯的高比探测率,远高于2-BHJ器件在0V时的2.72×1010Jones。这项工作表明,自组装膜的逐层层压可以有效地提高偏振光检测性能,为该领域的快速发展做出了重大贡献。
    To overcome the severe problems arising from the insufficient light absorption of ultrathin self-assembly active layers and the high cost use of atomic force deposition (ALD)-grown low-leakage-current transport layers, we successfully developed a low-cost, simple and facile strategy of floating-film transfer and multilayer lamination (FFTML) for constructing highly-efficient ALD-free broadband polarization-sensitive organic photodetectors (OPDs) with the two commonly used structures of donor/acceptor planar heterojunction (PHJ) and donor:acceptor multilayer bulk heterojunction (BHJ). It was found that the PHJ-based polarization-sensitive OPD by FFTML possesses a low dark current due to the high carrier injection barrier, indicating it is more suitable to be applied in low polarized light detection scenarios. In contrast, the BHJ-based device by FFTML has a higher spectral responsivity in the whole wavelength due to more photo-excitons transferred to the donor:acceptor interface and dissociated into photoexcited carrirers. Furthermore, the film thickness, which is tuned by increasing lamination number of BHJ layers, has a big effect on the polarization-sensitive photodetection performance. The polarization-sensitive 4-BHJ OPD by FFTML finally achieved a high specific detectivity of 8.33 × 1010Jones, which was much higher than 2.72 × 1010Jones for the 2-BHJ device at 0 V. This work demonstrates that layer-by-layer lamination of self-assembly films can effectively improve the polarized-light detection performance, contributing significantly to the rapid development of the field.
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  • 文章类型: Journal Article
    目前需要有机磷酸酯(OPE)抗氧化剂,因为它们有助于提高聚合物的质量,包括聚丙烯(PP)。在这项研究中,提出了一种从工业废水中有效提取双(2,4-二异丙苯基)季戊四醇二亚磷酸酯的整体方法。在采用固相萃取(SPE)技术时,使用高效液相色谱(HPLC)对回收的化合物进行全面分析,质谱(MS),热分析(TGA),傅里叶变换红外光谱(FTIR),和差示扫描量热法(DSC)。随后,纯化的双(2,4-二异丙苯基)季戊四醇二亚磷酸酯在掺入PP树脂后被评价为热氧化稳定剂。相对标准偏差(RSD),错误(Er),线性度(R2),和百分比(%)回收率分别小于2.6、2.5,显著大于0.9995,大于96%,分别,用于色谱方法和SPE的日间和日间测试。除了氯仿,由于所研究分析物的溶解度特性,这是必要的,使用环保溶剂,如甲醇和乙腈,是在这项研究的发展过程中考虑的。用FTIR对从工业废水中提取的OPE进行了表征,UV-Vis,DSC,TGA,MS,允许阐明双(2,4-二异丙苯基)季戊四醇二亚磷酸酯(BDPD)的结构。将回收的OPE与PP树脂混合,使其能够改善其热性能并最大程度地减少其热氧化降解。废水中有机磷阻燃剂(OPE)的浓度令人担忧,范围从1179.0到4709.6mgL-1。这些超过了水生生物的毒性阈值,强调全球环境风险。使用经过验证的固相萃取(SPE)技术,回收率超过94%,该研究通过去除有机污染物和支持循环经济原则来解决人们的担忧。恢复BDPD的高度经济和环境意义强调了紧急全球关注和干预的必要性。
    Organic phosphoester (OPE) antioxidants are currently required due to their contribution to enhancing the quality of polymers, including polypropylene (PP). In this research, an integral methodology is presented for the efficient extraction of bis(2,4-dicumylphenyl) pentaerythritol diphosphite from industrial wastewater. Upon employing the solid-phase extraction (SPE) technique, the recovered compound is subjected to a comprehensive analysis of the recovered compound using high-performance liquid chromatography (HPLC), mass spectrometry (MS), thermal analysis (TGA), Fourier transforms infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Subsequently, purified Bis(2,4-dicumylphenyl) pentaerythritol diphosphite was evaluated as a thermo-oxidative stabilizer after incorporation into PP resins. The relative standard deviation (RSD), Error (Er), linearity (R2), and percentage (%) recovery were less than 2.6, 2.5, more significant than 0.9995, and greater than 96%, respectively, for the inter-day and intra-day tests of the chromatographic method and the SPE. Except for chloroform, which was necessary due to the solubility properties of the investigated analyte, the use of environmentally friendly solvents, such as methanol and acetonitrile, was considered during the development of this research. The OPE extracted from industrial wastewater was characterized by FTIR, UV-Vis, DSC, TGA, and MS, allowing the elucidation of the structure of Bis(2,4-dicumylphenyl) pentaerythritol diphosphite (BDPD). The recovered OPE was mixed with PP resins, allowing it to improve its thermal properties and minimize its thermo-oxidative degradation. Organophosphorus flame retardant (OPE)\' concentration in wastewater is alarming, ranging from 1179.0 to 4709.6 mg L-1. These exceed toxicity thresholds for aquatic organisms, emphasizing global environmental risks. Using a validated solid-phase extraction (SPE) technique with over 94% recovery, the study addresses concerns by removing organic contaminants and supporting circular economy principles. The high economic and environmental significance of recovering BDPD underscores the need for urgent global attention and intervention.
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