Fourier-transform infrared spectroscopy

傅里叶变换红外光谱
  • 文章类型: Journal Article
    皮肤接触日常消费品中释放的化学物质越来越令人担忧,特别是对于那些易受无意的手口转移和相关化学品暴露风险的儿童。然而,由完整产品的微小颗粒引起的化学转移尚未得到充分解决。本研究的目的是通过测量嵌入的增塑剂(邻苯二甲酸酯及其替代品)的迁移率,确定皮肤接触时从完整的橡皮擦和笔握中释放颗粒的潜力。结果表明,在环境温度下皮肤接触时,橡皮擦(0.6-1.2×109)和笔柄(0.2-1.6×108)释放出数十亿个颗粒,尺寸主要小于1μm。橡皮擦渗滤液的成分与相应的散装橡皮擦的成分相同,通过傅里叶变换红外光谱和热解证实。迁移的疏水性增塑剂可用作从橡皮擦和笔柄释放颗粒的指示剂。对于橡皮擦和笔柄,颗粒释放的潜力与总增塑剂含量呈负相关(r=-0.51;p<0.05)。这些发现表明,从学校用品和配件中直接释放的颗粒可能是人体暴露于增塑剂的不可忽视的来源。
    Dermal exposure to chemicals released from daily consumer products is a rising concern, particularly for children who are susceptible to unintentional hand-to-mouth transfer and related chemical exposure risk. However, chemical transfer induced by tiny particles of intact products has yet to be adequately addressed. The objective of the present study was to determine the potentiality of particles release from intact erasers and pen grips upon dermal contact by measuring the migration rates of the embedded plasticizers (phthalates and its alternatives). The results showed that billions of particles were released from erasers (0.6-1.2 × 109) and pen grips (0.2-1.6 × 108) upon dermal contact at ambient temperature, with sizes mainly smaller than 1 μm. The composition of eraser leachates was identical to that of the corresponding bulk eraser, as confirmed by Fourier-transform infrared spectroscopy and pyrolysis. Migrated hydrophobic plasticizers may be used as indicators of particle release from erasers and pen grips. The potentiality of particle release was negatively correlated with the total plasticizer contents (r = -0.51; p < 0.05) for both erasers and pen grips. These findings indicated that particles directly released from school supplies and accessories could be a non-negligible source of human exposure to plasticizers.
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  • 文章类型: Journal Article
    铜绿假单胞菌是引起严重医院感染的最常见的条件致病菌之一,特别是碳青霉烯类。及时的流行病学监测可以极大地促进铜绿假单胞菌和许多致命病原体的感染控制。红外生物分型仪(IRBT),是一种新颖的实时打字工具,基于傅里叶变换红外(FTIR)光谱系统。综合建立和评价IRBT在铜绿假单胞菌菌株分型中的可行性至关重要。在目前的研究中,我们首先为其常规实验室应用建立了标准和方案,我们发现Mueller-Hinton琼脂平板比血琼脂平板具有更好的鉴别力。数据显示,在额外的0.025范围内,0.15的截断值是最佳的。其次,从2010年10月至2011年9月收集的27个临床分离的耐碳青霉烯类铜绿假单胞菌(CRPA)菌株通过比较IRBT与其他常用的分型方法来评估分型有效性。例如多位点序列分型(MLST),脉冲场凝胶电泳(PFGE)和基于全基因组测序(WGS)的分型。使用基于WGS的类型作为参考方法时,FTIR光谱(AR=0.757,SID=0.749)的分型方法比MLST和计算机血清分型(AR=0.544,SID=0.470)能更好地对铜绿假单胞菌菌株进行聚类。尽管PFGE表现出最高的歧视能力,PFGE与其他方法的一致性较低。最重要的是,这项研究证明了IRBT作为一种快速、低成本,用于检测CRPA菌株的实时分型工具。
    Pseudomonas aeruginosa is one of the most common opportunistic pathogens causing severe nosocomial infections for its patterns of multidrug resistance, particularly for carbapenems. Timely epidemiological surveillance could greatly facilitate infection control of P. aeruginosa and many deadly pathogens alike. IR Biotyper (IRBT), is a novel real-time typing tool, based on a Fourier-transform infrared (FTIR) spectroscopy system. It is critical to comprehensively establish and evaluate the feasibility of IRBT in P. aeruginosa strain typing. In the current study, we first established standards and schemes for its routine laboratory application, and we found that Mueller-Hinton agar plates give better discriminatory power than blood agar plates. Data showed that the cut-off value of 0.15 with an additional 0.025 range was optimal. Secondly, 27 clinically isolated carbapenem-resistant P. aeruginosa (CRPA) strains collected from October 2010 to September 2011 were evaluated for typing effectiveness by comparing IRBT to the other commonly used typing methods, such as multi-locus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS)-based typing. When using WGS-based typing as the reference method, the typing method of FTIR spectroscopy (AR = 0.757, SID = 0.749) could better cluster P. aeruginosa strains than MLST and in silico serotyping (AR = 0.544, SID = 0.470). Though PFGE showed the highest discriminatory power, low concordance was observed between PFGE and the other methods. Above all, this study demonstrates the utility of the IRBT as a quick, low-cost, real-time typing tool for the detection of CRPA strains.
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  • 文章类型: Journal Article
    大麦是一种诊断植物,经常用于研究重金属对土壤的污染,本研究通过盆栽试验探讨了大麦对镉(Cd)的解毒和耐受机理。我们调查了亚细胞分布,大麦叶片中Cd的化学形态和氧化损伤,结合透射电子显微镜和傅里叶变换红外光谱(FT-IR),Cd在细胞中的转化特性及毒性效应。结果表明,大麦根和芽中的生物积累因子分别为4.03-7.48和0.51-1.30。大麦通过将Cd存储在根中并减少其运输到芽中来减少毒性作用。与对照治疗(0mg/kg)相比,在300mg/kgCd处理下,叶片细胞壁部分中Cd的百分比从34.74%增加到38.41%;细胞器部分的百分比从24.47%增加到56.02%;可溶性部分的百分比从40.80%下降到5.57%。我们发现,69.13%的高毒性无机Cd和水溶性Cd被转化为毒性较低的果胶和蛋白质整合的Cd(50.20%)和不溶解的Cd磷酸盐(18.93%)。Cd的这种转化主要是由于它与-OH的结合,-NH,-CN,-C-O-C,和-C-O-P基团。过量Cd引起的过氧化物酶水平显著增加(P<0.05),丙二醛,和细胞膜通透性,从而破坏细胞膜并使Cd进入细胞器。叶绿体和线粒体被破坏,最终细胞内物质的代谢受到影响,导致毒性症状。我们的研究提供了对大麦镉耐受机制的细胞尺度洞察。
    Barley is a diagnostic plant that often used in the research of soil pollution by heavy metals, our research explored the detoxification and tolerance mechanism of cadmium(Cd) in barley through pot experiment. We investigated subcellular distribution, chemical forms and oxidative damage of Cd in barley leaves, combing with the transmission electron microscopy and Fourier-transform infrared spectroscopy(FT-IR) to further understand the translocation, transformation characteristics and toxic effect of Cd in cells. The results showed that, the bioaccumulation factors in roots and shoots of barley were ranged of 4.03-7.48 and 0.51-1.30, respectively. Barley reduces the toxic effects by storing Cd in the roots and reducing its transport to the shoots. Compared to the control treatment (0 mg/kg), the percentage of Cd in the cell wall fractions of leaves in 300 mg/kg Cd treatment increased from 34.74 % to 38.41 %; the percentage of the organelle fractions increased from 24.47 % to 56.02 %; and the percentage of soluble fraction decreased from 40.80 % to 5.57 %. We found that 69.13 % of the highly toxic inorganic Cd and water-soluble Cd were converted to less toxic pectates and protein-integrated Cd (50.20 %) and undissolved Cd phosphates (18.93 %). This conversion of Cd was mainly due to its combination with -OH, -NH, -CN, -C-O-C, and -C-O-P groups. Excessive Cd induced a significant (P < 0.05) increase in the levels of peroxidase, malondialdehyde, and cell membrane permeability, which damaged the cell membrane and allowed Cd to enter the organelles. The chloroplasts and mitochondria were destroyed, and eventually the metabolism of intracellular substances was affected, resulting in symptoms of toxicity. Our research provides cellular-scale insight into the mechanisms of Cd tolerance in barley.
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  • 文章类型: Journal Article
    为了评价绿豆分离蛋白(MPI)稳定乳状液的冻融稳定性及其与蛋白质结构的关系,对8个绿豆品种的蛋白质进行了比较。结果表明,从所有八个品种制备的MPIs主要由五个亚基带组成,白蛋白和球蛋白含量范围为188.4-310.3和301.1-492.7mg/g总蛋白,分别。蛋白质结构分析表明,无规卷曲结构(32.34-33.51%)占MPI二级结构的30%以上。同时,蛋白质性质分析显示乳化活性指数(EAI),乳化稳定性指数(ESI)和柔韧性值范围为6.735-8.598m2/g,分别为20.13-34.25%和0.125-0.182。对MPI乳液的冻融稳定性的测量表明,乳液暴露于多个冻融循环会导致乳液乳化指数显着不同。涂油,各种乳液的粒度和ζ电位值。此外,所有八种蛋白质乳液的稳定性随着每个冻融循环而降低,用光学显微照片证明。采用相关分析方法研究了原始结构之间的相关性,蛋白质的乳化特性和MPI乳液的冻融稳定性。相关分析结果显示白蛋白含量之间存在显著关系,分子量为26.9kDa的亚基条带和乳化性能与MPI乳液的冻融稳定性显着相关。因此,通过确定这些指标值,我们可以预测MPI稳定乳液的冻融稳定性。
    In order to evaluate the freeze-thaw stability of mung bean protein isolate (MPI)-stabilized emulsions and its relationship with protein structure, proteins of eight mung bean varieties were compared. The results revealed that MPIs prepared from all eight varieties were mainly composed of five subunit bands, with albumin and globulin content ranges of 188.4-310.3 and 301.1-492.7 mg/g total protein, respectively. Protein structural analysis revealed that random coil structure (32.34-33.51%) accounted for greater than 30% of MPI secondary structure. Meanwhile, analysis of protein properties revealed emulsifying activity index (EAI), emulsifying stability index (ESI) and flexibility value ranges of 6.735-8.598 m2/g, 20.13-34.25% and 0.125-0.182, respectively. Measurements of freeze-thaw stability of MPI emulsions demonstrated that exposures of emulsions to multiple freeze-thaw cycles resulted in significantly different emulsion creaming index, oiling-off, particle size and zeta potential values for the various emulsions. Moreover, the stabilities of all eight protein emulsions decreased with each freeze-thaw cycle, as demonstrated using optical micrographs. The correlation analysis method was used to study the correlation between the original structures, emulsifying properties of proteins and the freeze-thaw stability of MPI emulsions. Correlation analysis results revealed significant relationships between albumin content, subunit bands with a molecular weight of 26.9 kDa and emulsifying properties were significantly related to the freeze-thaw stability of MPI emulsion. Thus, by determining these indicator values, we can predict the freeze-thaw stability of MPI-stabilized emulsions.
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  • 文章类型: Journal Article
    宫颈癌是最常见的妇科恶性肿瘤。.早期准确识别宫颈癌患者的分期可以大大提高治愈率。在这项研究中,从宫颈癌患者收集血清样本数据,CIN(宫颈上皮内瘤变)I,CINII,使用FT-IR(傅立叶变换红外光谱)技术的CINIII和子宫肌瘤。采用粒子群算法设计宫颈癌早期筛查的PSO-CNN模型,自动构建可变层数、可变层类参数的CNN结构。实验结果表明,与经典的Lenet相比,PSO-CNN是最好的,AlexNet,VGG16和GoogLeNet深度学习模型,PSO-CNN对5类样本的判别准确率可达87.2%。本研究表明,FT-IR技术结合PSO-CNN模型在非侵入性、快速准确地识别宫颈癌患者,为其他疾病的智能诊断提供参考。
    Cervical cancer is the most common gynecological malignancy.. Early and accurate identification of the stage of cervical cancer patients can greatly improve the cure rate. In this study, serum sample data were collected from patients with cervical cancer, CIN (cervical intraepithelial neoplasia) I, CIN II, CIN III and hysteromyoma using FT-IR (Fourier-transform infrared spectroscopy) technology. PSO-CNN model for early screening of cervical cancer was designed using a particle swarm algorithm to automatically build a CNN structure with variable number of layers and variable layer class parameters. The experimental results showed that PSO-CNN was the best compared with the classical Lenet, AlexNet, VGG16 and GoogLeNet deep learning models, and the accuracy of PSO-CNN in discriminating five types of samples can reach 87.2%. This study showed that FT-IR technology combined with PSO-CNN model had great potential for non-invasive, rapid and accurate identification of patients with cervical cancer, and can provide a reference for intelligent diagnosis of other diseases.
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  • 文章类型: Journal Article
    背景:秋葵豆荚含有热敏物质,如酚类化合物和其他植物化学物质,当秋葵豆荚进行热处理时可以降解。了解高湿度热空气冲击烫漂(HAIB)对秋葵豆荚多糖和植物化学物质的物理化学性质变化的影响非常重要,因为过度烫漂可能导致细胞膜破裂和生物活性化合物的变化在长时间暴露于热处理下。因此,本研究旨在研究HAIB对秋葵豆荚中果胶和植物化学物质理化性质变化的影响。
    结果:HAIB时间和提取方法均影响其理化特性和生物活性。经受HHAIB的果胶级分由聚半乳糖醛酸组成,鼠李糖半乳糖醛酸,葡甘露聚糖,半乳聚糖,甘露糖,阿拉伯糖,鼠李糖,果胶酸钙和阿拉伯半乳聚糖。总酚的含量,HHAIB期间提取物的总黄酮和抗氧化活性大多增加(即高达19.0%,13.2%和35.3%,分别)。然而,HHAIB降低了秋葵豆荚的叶绿素a(高达55.7%)和番茄红素(高达52.6%)的含量。
    结论:获得的知识可能有助于更好地理解和优化基于HAIB治疗的技术。HHAIB处理过的秋葵在不同的应用中可能是一个有前途的天然替代品,包括由于多糖和多酚的丰富而用作食品或非食品系统中某些成分的替代品,以及高抗氧化性能。©2022化学工业学会。
    BACKGROUND: Okra pods contain heat-sensitive substances, such as phenolic compounds and other phytochemicals that can be degraded when okra pods are subjected to heat treatment. The understanding of the impact of high humidity hot air impingement blanching (HHAIB) on the changes in physicochemical properties of polysaccharides and phytochemicals of okra pods is of great importance because over-blanching may result in cell membrane disruption and changes in biologically active compounds under prolonged exposure to the thermal treatment. Therefore, the present study aimed to investigate the effect of HHAIB on the changes in physicochemical properties of pectins and phytochemicals extracted from okra pods.
    RESULTS: Both the HHAIB time and method of extraction influenced their physicochemical characteristics and biological activity. Pectin fractions subjected to HHAIB were composed of polygalacturonic acid, rhamnogalacturonan, glucomannan, galactan, mannose, arabinose, rhamnose, calcium pectate and arabinogalactan. The contents of total phenolics, total flavonoids and antioxidant activity of extracts mostly increased during HHAIB (i.e. up to 19.0%, 13.2% and 35.3%, respectively). However, HHAIB reduced the chlorophyll-a (up to 55.7%) and lycopene (up to 52.6%) contents of okra pods.
    CONCLUSIONS: The acquired knowledge may be useful for better understanding and optimization of technologies based on HHAIB treatment. The HHAIB treated okra can be a promising natural alternative in different applications, including its use as a replacement of some ingredients in food or non-food systems as a result of richness in polysaccharides and polyphenols, as well as high antioxidant properties. © 2022 Society of Chemical Industry.
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  • 文章类型: Journal Article
    堆肥是一种环保而有效的处理绿色废物(GW)的方法,但是GW的传统堆肥速度很慢,会导致许多营养素的损失和劣质堆肥产品。在这项研究中,成熟堆肥(MC),它可以作为廉价和容易获得的微生物接种剂,以15%、20%、25%和30%(w/w,干重基础)(处理分别为T2-T5);GW为0.5%(v/w,干重)商业微生物接种物用作T1,没有任何微生物接种物的GW用作对照。根据以下堆肥特性确定产生最高质量堆肥的处理:温度,堆积密度,孔隙度,pH值,电导率,有机物和营养物质的含量,傅里叶变换红外光谱数据,和植物毒性。结果表明,添加25%MC仅在40天内就获得了最佳质量的产品。
    Composting is an environmentally friendly and effective way to dispose of green waste (GW), but traditional composting of GW is slow and results in the loss of many nutrients and a poor-quality compost product. In this study, mature compost (MC), which may function as an inexpensive and readily available microbial inoculant, was added to GW at 15, 20, 25, and 30% (w/w, dry weight basis) (treatments T2-T5, respectively); GW with 0.5% (v/w, dry weight basis) commercial microbial inoculum served as T1, and GW without any microbial inoculant served as the control. The treatment that produced the highest quality compost was determined based on the following compost properties: temperature, bulk density, porosity, pH, electric conductivity, contents of organic matter and nutrients, Fourier-transform infrared spectroscopy data, and phytotoxicity. The results showed that addition of 25% MC resulted in the best quality product in only 40 days.
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  • 文章类型: Journal Article
    Tea cream, produced by interactions among tea ingredients, is undesirable in tea beverage industry. The interaction between bovine serum albumin (BSA) and theaflavin-3,3\'-digallate (TFDG, an important component in tea cream and functional substance of black tea) was investigated by fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorption spectroscopy, synchronous fluorescence spectroscopy, fourier-transform infrared (FT-IR) spectroscopy, and molecular docking technique. Multi-spectroscopic experiments demonstrated that TFDG interacted with BSA via static quenching, and the microenvironment around BSA became more hydrophobicity. FT-IR showed that the α-helix of BSA was increased when binding with TFDG. Thermodynamic parameters and molecular docking demonstrated that hydrophobic interactions and hydrogen bonds dominated the interaction between TFDG and BSA. The mechanism proposed in this research could further develop some nanoparticles to excellent biochemical properties while reducing the formation of tea cream, and explore the potential of BSA as transport carrier for TFDG.
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  • 文章类型: Journal Article
    A dataset in this report is regarding an article, \"A detailed ellipsometric porosimetry and positron annihilation spectroscopy study of porous organosilicate glass films with various ratios of methyl terminal and ethylene bridging groups\" [1]. The data of porous organosilicate glass (OSG) low-k films was obtained by Fourier-Transform Infrared spectroscopy (FTIR), Ellipsometric Porosimetry (EP), Photoluminescence (PL) Spectroscopy. The data shows that the mechanical properties of OSG low-k films are principally controlled by introducing both terminal methyl and bridging organic groups, and porosity with proper pore size. The dataset presented here gives additional details regarding properties of carbon bridged OSGs presented in the paper [1]. Also, the data may give the impact of both terminal methyl and bridging ethylene groups on as deposited and thermally cured OSG films. Particularly, we added some details about FTIR, EP (especially related to calculation of the internal surface area) and UV induced luminescence. The data allow to test experimental and theoretical investigations of OSG low-k materials that might use in microelectronic fabrication industry and also might be used to extend beyond the analysis reported in the accompanying manuscript, and may aid for other applications of OSG materials.
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  • 文章类型: Journal Article
    The thermal decomposition process of 2,6-diamino-3,5-dinitropyrazine-1-oxide(LLM-105)under several constant temperatures (100 °C, 115 °C, 130 °C, and 145 °C) have been studied by a multi-channel in-situ reaction system. Almost 1000 spectra were obtained within 24 days by Fourier-transform infrared spectroscopy (FT-IR). The thermal decomposition activation energies (Eα) of C-NH2 and C-NO2 in LLM-105 were calculated by the Arrhenius equation to be 89.65 and 145.09 kJ mol-1, respectively. The thermal decomposition process of LLM-105 under long-term constant temperature is divided into two paths: intramolecular H-transfer and C-NO2 partition. It is feasible to study the aging process of materials using a combination of a multi-channel in-situ reaction system and FT-IR, which can effectively monitor the evolution of structure.
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