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1.
Kaitlin A. Doucette Prangthong Chaiyasit Donn L. Calkins Kayli N. Martinez Cameron Van Cleave Callan A. Knebel Anan Tongraar Debbie C. Crans 《International journal of molecular sciences》2021,22(1)
The interactions of amino acids and peptides at model membrane interfaces have considerable implications for biological functions, with the ability to act as chemical messengers, hormones, neurotransmitters, and even as antibiotics and anticancer agents. In this study, glycine and the short glycine peptides diglycine, triglycine, and tetraglycine are studied with regards to their interactions at the model membrane interface of Aerosol-OT (AOT) reverse micelles via 1H NMR spectroscopy, dynamic light scattering (DLS), and Langmuir trough measurements. It was found that with the exception of monomeric glycine, the peptides prefer to associate between the interface and bulk water pool of the reverse micelle. Monomeric glycine, however, resides with the N-terminus in the ordered interstitial water (stern layer) and the C-terminus located in the bulk water pool of the reverse micelle. 相似文献
2.
Single-metal high-temperature solid sorbents for syngas cleaning using Mn, Ca, Fe, Cu, or Mo supported on γ-Al2O3 were synthesized, characterized, and tested in a fixed-bed reactor. H2S and SO2 concentrations in the gas after treatment at T = 400 to 700 °C were compared with thermodynamic calculations. The Mn-based sorbent showed the best ability to achieve a low sulfur residual in the gas, especially at temperatures above 600 °C. Sorbents with Fe, Cu, and Mo gave SO2 formation in the initial phase, but this could be avoided by a pre-reduction treatment of the sorbent material. 相似文献
3.
SeyedHosein Payandeh Daniel Rentsch Zbigniew Łodziana Ryo Asakura Laurent Bigler Radovan Černý Corsin Battaglia Arndt Remhof 《Advanced functional materials》2021,31(18):2010046
Hydroborate-based solid electrolytes have recently been successfully employed in high voltage, room temperature all-solid-state sodium batteries. The transfer to analogous lithium systems has failed up to now due to the lower conductivity of the corresponding lithium compounds and their high cost. Here LiB11H14 nido-hydroborate as a cost-effective building block and its high-purity synthesis is introduced. The crystal structures of anhydrous LiB11H14 as well as of LiB11H14-based mixed-anion solid electrolytes are solved and high ionic conductivities of 1.1 × 10−4 S cm−1 for Li2(B11H14)(CB11H12) and 1.1 × 10−3 S cm−1 for Li3(B11H14)(CB9H10)2 are obtained, respectively. LiB11H14 exhibits an oxidative stability limit of 2.6 V versus Li+/Li and the proposed decomposition products are discussed based on density functional theory calculations. Strategies are discussed to improve the stability of these compounds by modifying the chemical structure of the nido-hydroborate cage. Galvanostatic cycling in symmetric cells with two lithium metal electrodes shows a small overpotential increase from 22.5 to 30 mV after 620 h (up to 0.5 mAh cm−2), demonstrating that the electrolyte is compatible with metallic anodes. Finally, the Li2(B11H14)(CB11H12) electrolyte is employed in a proof-of-concept half cell with a TiS2 cathode with a capacity retention of 82% after 150 cycles at C/5. 相似文献
4.
Weronika Gonciarz ukasz Lechowicz Mariusz Urbaniak Wiesaw Kaca Magdalena Chmiela 《International journal of molecular sciences》2021,22(1)
Infections due to Gram-negative bacteria Helicobacter pylori may result in humans having gastritis, gastric or duodenal ulcer, and even gastric cancer. Investigation of quantitative changes of soluble biomarkers, correlating with H. pylori infection, is a promising tool for monitoring the course of infection and inflammatory response. The aim of this study was to determine, using an experimental model of H. pylori infection in guinea pigs, the specific characteristics of infrared spectra (IR) of sera from H. pylori infected (40) vs. uninfected (20) guinea pigs. The H. pylori status was confirmed by histological, molecular, and serological examination. The IR spectra were measured using a Fourier-transform (FT)-IR spectrometer Spectrum 400 (PerkinElmer) within the range of wavenumbers 3000–750 cm−1 and converted to first derivative spectra. Ten wavenumbers correlated with H. pylori infection, based on the chi-square test, were selected for a K-nearest neighbors (k-NN) algorithm. The wavenumbers correlating with infection were identified in the W2 and W3 windows associated mainly with proteins and in the W4 window related to nucleic acids and hydrocarbons. The k-NN for detection of H. pylori infection has been developed based on chemometric data. Using this model, animals were classified as infected with H. pylori with 100% specificity and 97% sensitivity. To summarize, the IR spectroscopy and k-NN algorithm are useful for monitoring experimental H. pylori infection and related inflammatory response in guinea pig model and may be considered for application in humans. 相似文献
5.
以某酸性气制硫酸装置酸性气缓冲罐为例,进行外部安全防护距离设计,结合当地多种气象,使用PHAST软件和LEAK软件进行H_2S气体扩散和爆炸计算,扩散结果应用于周边人员集中场所的防毒设计以及企业的应急救援,H_2S爆炸计算结果应用于周边人员集中场所建构筑物的抗爆设计,并和《石油化工工厂布置设计规范》(GB 50984-2014)中的建议值进行比对。 相似文献
6.
Avneet Kaur Neha Bhardwaj Amanpreet Kaur Km Abida Tejo Prakash Nagaraja Amjad Ali Ranjana Prakash 《Journal of the American Oil Chemists' Society》2021,98(2):139-147
Epoxidized methyl esters (EMO) with their high oxirane ring reactivity, acts as a raw material in the synthesis of various industrial chemicals including polymers, stabilizers, plasticizers, glycols, polyols, carbonyl compounds, biolubricants etc. EMO has been generally quantified by the gas chromatography (GC) and high-performance liquid chromatography (HPLC) techniques. Taking into the account of the limitations of these techniques, two qHNMR-based equations have been proposed for the quantification of EMO in the mixture of EMO and methylesters (MO). The validity of the proposed method was determined using standard mixtures of MO and EMO having different molar concentrations. The developed equations have been applied on the samples of EMO prepared from oleic acid in two-step process viz., esterification followed by epoxidation. The qHNMR-based EMO quantification showed acceptable agreement with the results obtained from HPLC analysis. 相似文献
7.
Liu Yang Pengfei Yu Wenyuan Li Fengliang Cao Xin Jin Sheng Xue Xianglong Zhang Tingwei Zhang Mingbo Wu Wenting Wu 《American Institute of Chemical Engineers》2022,68(9):e17760
Hydrogen peroxide (H2O2) has been listed as one of the 100 most important chemicals in the world. However, huge amount of residual H2O2 is hard to timely decomposed into O2 and H2O under acidic condition, easily resulting in explosion hazard. Here, we reported a core–shell structure catalyst, that is graphene with Co N structure encapsulated Co nanoparticles. Co N graphene shell serves as the active site for the H2O2 decomposition, and Co core further enhance this decomposition. Benefiting from it, the H2O2 decomposition were close to 100% after 6 cycles without pH adjustment, which increased 6 orders of magnitude compared with no catalyst. At the same time, the O2 generation reached 99.67% in 2 h with little metal leaching, and ·OH has been greatly inhibited to only 0.08%. This work can cleanly remove H2O2 with little deep oxidation and protect the process of H2O2 utilization to achieve a safer world. 相似文献
8.
This work describes facile synthesis of a porous polymeric material ( T-HCP ) using readily available reagents. Specifically, T-HCP is a thermally stable and hypercrosslinked polymer (HCP) that is essentially microporous with a high BET specific surface area (940 m2 g?1). Triptycene based polymers are known to feature internal free volume. Thus, the incorporation of triptycene units and extensive crosslinking by an external cross-linker in T-HCP makes it a promising adsorbent for small gas capture applications. Experimental results show that T-HCP demonstrated good CO2 capture capacity of 132 mg g?1 (273 K, 1 bar). Molecular hydrogen storage capacity of T-HCP is estimated to be 17.7 mg g?1 (77 K, 1 bar). T-HCP revealed high CO2/N2 selectivity (up to 63) as well as promising CO2/CH4 (up to 9.1) selectivity suggesting its potential applicability for CO2 separation from flue and natural gases. 相似文献
9.
吐哈盆地葡北地区“两宽一高”地震勘探技术及应用效果 总被引:1,自引:0,他引:1
吐哈盆地台北凹陷圈闭落实的准确度和储层分布预测的精度一直是制约该区油气发现的关键因素。通过可控震源“两宽一高”地震采集、OVT域时间偏移、地质导向深度偏移初始模型建立及各向异性深度偏移迭代处理,在地震资料的信噪比、频带宽度和分辨率等方面明显提高的基础上,以高精度层序地层学为指导,基于高分辨率地震资料与钻井、测井资料的综合分析,识别出侏罗系6个三级层序,在三级层序格架内将研究区七克台组底部和三间房组顶部砂体识别为两个连续上升半旋回四级层序;通过构造几何属性分析及精细构造分析,揭示了本区“四带、两凹”的构造格局及形成机制;以宽频带多种反演技术为手段,对含油气层段的七克台组和三间房组砂体分布进行了预测;在综合构造分析、储层分析和油藏成藏规律分析的基础上,提出本区油气沿构造带脊线聚集,断裂系统是油气运移的优势路径,七克台组、三间房组储层在葡北构造带发育,向玉果构造带和胜北次凹减薄尖灭,葡北构造带与玉果构造带结合部位的,具有鼻状构造背景的岩性圈闭是获得油气突破的有利地区。 相似文献
10.
《International Journal of Hydrogen Energy》2019,44(35):19067-19079
In order to maximise European, national and regional research and innovation potential the European Union is investing in these fields through different funding mechanisms such as the ESIF or H2020 programme. This investment plan is part of the European 2020 strategy, where the concept of Smart Specialisation is also included.Smart Specialisation is an innovation policy concept designed to promote the efficient and effective use of public investment in regional innovation in order to achieve economic growth. The Smart Specialisation Platform was created to support this concept by assisting regions and Member States in developing, implementing and reviewing their research and innovation Smart Specialisation strategies.The Smart Specialisation Platform comprises several thematic platforms. The thematic Smart Specialisation Platform on energy (S3PEnergy) is a joint initiative of three European Commission services: DG REGIO, DG ENER, and the Joint Research Centre (JRC). The main objective of the S3PEnergy is to support the optimal and effective uptake of the Cohesion Policy funds for energy, and to better align energy innovation activities at national, local and regional level through the identification of the technologies and innovative solutions that support in the most cost-effective way the EU energy policy priorities.In the particular case of hydrogen technologies, the activities of the platform are mainly focused on supporting the new Fuel Cells and Hydrogen Joint Undertaking (FCH JU) initiative involving regions and cities. To date, more than 80 European cities and regions have committed to participate in this initiative through the signature of a Memorandum of Understanding, and more participants are expected to join. S3PEnergy is helping in the identification of potential combination of H2020 funding (provided through FCH JU) and ESIF.To identify potential synergies among these two funding sources, a mapping of the different ESIF opportunities has been performed. In order to map these opportunities, Operational Programmes (OPs) and research and innovation strategies for Smart Specialisation (RIS3) of the different European regions and Member States were analysed. The results of this mapping and analysis are presented in this paper. 相似文献