functionalization

Functionalization
  • 文章类型: Journal Article
    基于二维(2D)结构的新型电极材料的发现对于碱金属离子电池至关重要。在这里,我们进行了第一原理计算来研究功能化的MXenes,Mo2BT2(T=O,S),它们也被认为是基于B的MXenes,或者叫MBenes,作为锂离子电池和其他电池的潜在阳极材料。原始和T终止的Mo2BT2(T=O,S)单层显示出具有较高电子电导率的金属特性,并且具有固有偶极矩的热力学稳定。Mo2BO2和Mo2BS2单层均表现出高的理论Li/Na/K存储容量和低的离子扩散势垒。这些发现表明,功能化的Mo2BT2(T=O,S)单层有望为高性能碱离子电池设计可行的阳极材料。
    The discovery of novel electrode materials based on two-dimensional (2D) structures is critical for alkali metal-ion batteries. Herein, we performed first-principles computations to investigate functionalized MXenes, Mo2BT2(T = O, S), which are also regarded as B-based MXenes, or named as MBenes, as potential anode materials for Li-ion batteries and beyond. The pristine and T-terminated Mo2BT2(T = O, S) monolayers reveal metallic character with higher electronic conductivity and are thermodynamically stable with an intrinsic dipole moment. Both Mo2BO2and Mo2BS2monolayers exhibit high theoretical Li/Na/K storage capacity and low ion diffusion barriers. These findings suggest that functionalized Mo2BT2(T = O, S) monolayers are promising for designing viable anode materials for high-performance alkali-ion batteries.
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  • 文章类型: Journal Article
    使用原子力显微镜评估植物脂质转移蛋白Prup3与植物鞘氨醇之间的相互作用。将植物鞘氨醇共价固定在DeepTipTM探针上,并将Prup3共价固定在MicroDeckTM功能化的底物上。检索两种分子之间的单分子相互作用事件并对其进行分类,并计算每种鉴定类型的分布。通过将特定的Prup3-植物鞘氨醇相互作用事件的数量与记录的曲线总数进行比较,发现成功率超过70%。进一步对各种类型的曲线之间建立的分布进行分析,以区分那些主要用于在亲和原子力显微镜的背景下评估植物鞘氨醇(传感器分子)和Prup3(目标分子)之间的识别的曲线。以及那些需要相互作用细节的东西,可以在力光谱学的背景下使用。这些官能化探针和底物成功应用于表征该系统的低强度疏水相互作用特征清楚地表明了利用该方法具有非常广泛的不同感兴趣的生物分子的潜力。以单分子分辨率表征分子组装事件的可能性为进入分子仿生领域提供了有利的程序。
    The interaction between the plant lipid transfer protein Pru p 3 and phytosphingosine was assessed using an atomic force microscope. Phytosphingosine was covalently immobilized on DeepTipTM probes and Pru p 3 on MicroDeckTM functionalized substrates. Single-molecular interaction events between both molecules were retrieved and classified and the distribution for each one of the identified types was calculated. A success rate of over 70% was found by comparing the number of specific Pru p 3-phytosphingosine interaction events with the total number of recorded curves. The analysis of the distribution established among the various types of curves was further pursued to distinguish between those curves that can mainly be used for assessing the recognition between phytosphingosine (sensor molecule) and Pru p 3 (target molecule) in the context of affinity atomic force microscopy, and those that entail details of the interaction and might be employed in the context of force spectroscopy. The successful application of these functionalized probes and substrates to the characterization of the low-intensity hydrophobic interaction characteristic of this system is a clear indication of the potential of exploiting this approach with an extremely wide range of different biological molecules of interest. The possibility of characterizing molecular assembly events with single-molecule resolution offers an advantageous procedure to plough into the field of molecular biomimetics.
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  • 文章类型: Journal Article
    使用草酸对锶基MOF进行了简单的改性,以制备MTSr-OXMOF,它被用作消除152+154Eu放射性同位素的潜在物质。使用各种分析技术来表征MTSr-OX-MOF。制备的MOF具有杆状结构,BET表面积为101.55m2g-1。批量吸附实验用于研究MTSr-OX-MOF对152154Eu放射性核素的吸附性能,这些放射性核素具有不同的参数,例如pH值,接触时间,初始152+154Eu浓度,离子强度,对温度和温度进行了仔细检查,以确定去除152154Eu的最佳条件。MTSr-OX-MOF在消除152154Eu方面表现出优异的效果,在pH3.5时的最大吸附能力为234.72mgg-1。拟合伪二阶模型和Langmuir模型的动力学正确描述了吸附机理。仔细检查了热力学变量,证明152+154Eu吸附是吸热的,也是自发的。已经发现MTSr-OX-MOF是比许多其他吸附剂对152+154Eu显著更有效的吸附剂。当应用于真正的活性废物时,MTSr-OX-MOF对多种放射性核素表现出优异的去除性能。因此,MTSr-OX-MOF可以被认为是从活性废物中纯化152+154Eu的有吸引力的解决方案。
    A facile modification of a strontium-based MOF using oxalic acid was carried out to prepare MTSr-OX MOF, which was used as a potential substance for eliminating 152+154Eu radioisotopes. Various analytical techniques were used to characterize MTSr-OX-MOF. The prepared MOF had a rod-like structure with a BET surface area of 101.55 m2 g-1. Batch sorption experiments were used to investigate the sorption performance of MTSr-OX-MOF towards 152+154Eu radionuclides where different parameters like pH, contact time, initial 152+154Eu concentration, ionic strength, and temperature were scrutinized to determine the optimum conditions for 152+154Eu removal. MTSr-OX-MOF showed superior effectiveness in the elimination of 152+154Eu with a maximum sorption capacity of 234.72 mg g-1 at pH 3.5. Kinetics fitted with the pseudo-second-order model and the Langmuir model correctly described the sorption mechanism. The thermodynamic variables were carefully examined, demonstrating that the 152+154Eu sorption was endothermic as well as spontaneous. The MTSr-OX-MOF has been found to be a significantly more effective sorbent towards 152+154Eu than that of many other adsorbents. When applied to real active waste, MTSr-OX-MOF demonstrated excellent removal performance for a wide range of radionuclides. As a result, the MTSr-OX-MOF can be recognized as an attractive solution for the 152+154Eu purification from active waste.
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  • 文章类型: Journal Article
    膜的渗透选择性对于开发具有两个氧化还原对的电化学储能装置至关重要。例如氧化还原液流电池(RFB)。在RFB中,Br3-/Br-耦合通常用作阴极电解液,可以越过阳极电解液,限制电池的寿命。自然,选择性渗透膜的开发对于RFB的成功至关重要,因为最先进的全氟磺酸(PFSA)成本太高。这项研究调查了氧化石墨烯(GO)的膜,聚乙烯吡咯烷酮(PVP),和咪唑(Im)作为粘合剂和接头,分别。将GO膜与标准PFSA膜在离子电导率(Na+)和选择透过性(排除Br-)方面进行比较。在四电极系统中,通过电化学阻抗谱和两室扩散池的选择性来评估离子传导。我们的发现表明GO膜达到与标准PFSA膜相当的电导率和选择性透过性。
    Permselectivity of a membrane is central for the development of electrochemical energy storage devices with two redox couples, such as redox flow batteries (RFBs). In RFBs, Br3-/Br- couple is often used as a catholyte which can cross over to the anolyte, limiting the battery\'s lifetime. Naturally, the development of permselective membranes is essential to the success of RFBs since state-of-the-art perfluorosulfonic acid (PFSA) is too costly. This study investigates membranes of graphene oxide (GO), polyvinylpyrrolidone (PVP), and imidazole (Im) as binder and linker, respectively. The GO membranes are compared to a standard PFSA membrane in terms of ionic conductivity (Na+) and permselectivity (exclusion of Br-). The ionic conduction is evaluated from electrochemical impedance spectroscopy and the permselectivity from two-compartment diffusion cells in a four-electrode system. Our findings suggest that the GO membranes reach conductivity and permselectivity comparable with standard PFSA membranes.
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  • 文章类型: Journal Article
    在由工业金属涂层产生的流出物中存在高浓度的金属离子是众所周知的事实。大多数时候,这样的金属离子,一旦他们到达环境,大大有助于其退化。因此,至关重要的是,在这些废水排放到环境中之前,金属离子的浓度必须(尽可能地)降低,以尽量减少对生态系统质量的负面影响。在所有可用于降低金属离子浓度的方法中,吸附是最可行的选择之一,由于其高效率和低成本。此外,由于许多工业废物具有吸附特性,这种方法符合循环经济的原则。基于这些考虑,在这项研究中,芥末废物生物质(由油提取产生)用工业聚合硫代氨基甲酸酯(METALSORB)官能化,并用作吸附剂以去除Cu(II),来自水性介质的Zn(II)和Co(II)离子。发现芥菜废物生物质官能化的最佳条件是:混合比生物质:METASORB=1g:1.0mL,温度为30°C。功能化吸附剂(MET-MWB)的实验吸附容量为0.42mmol/g的Cu(II),Zn(II)为0.29mmol/g,Co(II)为0.47mmol/g,它们是在以下条件下获得的:pH为5.0,吸附剂为5.0g/L,温度为21°C。等温线和动力学曲线的建模以及从解吸过程获得的结果的分析证明了该吸附剂在处理被金属离子污染的废水中的有用性。此外,对实际废水样品的测试强调了MET-MWB用于大规模应用的潜力。
    The presence of high concentrations of metal ions in effluents resulting from industrial metal coatings is a well-known fact. Most of the time, such metal ions, once they reach the environment, significantly contribute to its degradation. Therefore, it is essential that the concentration of metal ions is reduced (as much as possible) before such effluents are discharged into the environment to minimize the negative impact on the quality of the ecosystems. Among all methods that can be used to reduce the concentration of metal ions, sorption is one of the most viable options due to its high efficiency and low cost. Moreover, due to the fact that many industrial wastes have sorbent properties, this method is in accordance with the principles of circular economy. Based on these considerations, in this study, mustard waste biomass (resulting from oil extraction) was functionalized with an industrial polymeric thiocarbamate (METALSORB) and used as a sorbent to remove Cu(II), Zn(II) and Co(II) ions from aqueous media. The best conditions for the functionalization of mustard waste biomass were found to be: mixing ratio biomass: METASORB = 1 g: 1.0 mL and a temperature of 30 °C. The experimental sorption capacities of functionalized sorbent (MET-MWB) were 0.42 mmol/g for Cu(II), 0.29 mmol/g for Zn(II) and 0.47 mmol/g for Co(II), which were obtained under the following conditions: pH of 5.0, 5.0 g sorbent/L and a temperature of 21 °C. The modeling of isotherms and kinetic curves as well as the analysis of the results obtained from desorption processes demonstrate the usefulness of this sorbent in the treatment of effluents contaminated with metal ions. In addition, tests on real wastewater samples highlight the potential of MET-MWB for large-scale applications.
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  • 文章类型: Journal Article
    在生物催化领域,实施可持续过程,如酶固定化或使用环保溶剂,像深共晶溶剂(DES)是至关重要的。在这项工作中,酪氨酸酶是从新鲜蘑菇中提取的,用于无载体固定化,以制备非磁性和磁性交联酶聚集体(CLEA)。对制备的生物催化剂进行了表征,并在许多DES水溶液中评估了游离酪氨酸酶和酪氨酸酶磁性CLEAs(mCLEAs)的生物催化和结构特征。结果表明,作为共溶剂的DES的性质和浓度显著影响酪氨酸酶的催化活性和稳定性,与未固定化酶相比,固定化酶的活性提高了3.6倍。生物催化剂在-20°C下储存1年后保持其初始活性的100%和在5个重复循环后其活性的90%。在DES存在下,酪氨酸酶mCLEAs进一步应用于咖啡酸对壳聚糖的均相改性。在存在10%v/vDES[Bet:Gly(1:3)]的情况下,生物催化剂在用咖啡酸对壳聚糖进行官能化方面表现出很大的能力,增强膜的抗氧化活性。
    In the field of biocatalysis, the implementation of sustainable processes such as enzyme immobilization or employment of environmentally friendly solvents, like Deep Eutectic Solvents (DESs) are of paramount importance. In this work, tyrosinase was extracted from fresh mushrooms and used in a carrier-free immobilization towards the preparation of both non-magnetic and magnetic cross-linked enzyme aggregates (CLEAs). The prepared biocatalyst was characterized and the biocatalytic and structural traits of free tyrosinase and tyrosinase magnetic CLEAs (mCLEAs) were evaluated in numerous DES aqueous solutions. The results showed that the nature and the concentration of the DESs used as co-solvents significantly affected the catalytic activity and stability of tyrosinase, while the immobilization enhanced the activity of the enzyme in comparison with the non-immobilized enzyme up to 3.6-fold. The biocatalyst retained the 100% of its initial activity after storage at -20 °C for 1 year and the 90% of its activity after 5 repeated cycles. Tyrosinase mCLEAs were further applied in the homogeneous modification of chitosan with caffeic acid in the presence of DES. The biocatalyst demonstrated great ability in the functionalization of chitosan with caffeic acid in the presence of 10% v/v DES [Bet:Gly (1:3)], enhancing the antioxidant activity of the films.
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  • 文章类型: Journal Article
    氮化硼纳米片(BNNS)和氧化石墨烯(GO)作为单一填料可以有效提高复合材料的导热性,研究了BNNS与GO的协同作用机制。在这项研究中,BNNS首先进行了表面官能化和多尺寸(50nm,200nm,500nm)修饰的BNNS(A-BN)通过非共价键合相互作用与GO连接,形成交联结构。然后,以A-BN和GO为热填料和载体材料吸附共晶相变材料(PCM)制备复合相变材料(CPCM)。表征结果表明,小尺寸A-BN更容易形成密集的热网络,PCM之间具有良好的兼容性和界面连通性,A-BN,去,确保PCM可以存储在网络中而不会泄漏。当BNNS的尺寸大于200nm时,A-BN获得的热导率优势不再明显,抑制了CPCM的相变行为。总的来说,制备的CPCM具有理想的热响应和热稳定性,非常适合储能和热管理应用。
    Boron nitride nanosheet (BNNS) and graphene oxide (GO) as a single filler can effectively improve the thermal conductivity of the composites, and the synergistic mechanism of BNNS and GO was investigated in this paper. In this study, BNNS was first surface-functionalized and the multi-sized (50 nm, 200 nm, 500 nm) modified BNNS (A-BN) were attached to GO through non-covalent bonding interactions to form a cross-linked structure. Then, A-BN and GO were used as thermal fillers and support material adsorption eutectic phase change materials (PCMs) to prepare composite phase change material (CPCM). Characterization results show that small-size A-BN was more likely to form dense thermal networks with good compatibility and interface connectivity between PCMs, A-BN, and GO, ensuring that PCMs can be stored in the network without leaking. When the size of the BNNS was greater than 200 nm, the advantage of thermal conductivity obtained by A-BN was no longer obvious, and the phase change behavior of CPCM was inhibited. In general, the prepared CPCM has the ideal thermal response and thermal stability, which is very suitable for energy storage and thermal management applications.
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  • 文章类型: Journal Article
    异双金属三层配合物[(Cp*Fe)(Cp\'\'\'Co)(μ,η5:η4-P5)](1)被主族亲核试剂官能化,随后亲电猝灭或氧化。与第14族亲核试剂的反应1显示出不同的有机取代P5R中间甲板,具体取决于所用碱金属有机化合物的空间和电子效应(2:R=tBu;3:R=Me)。Further,与15组亲核试剂,第一个结构表征的与膦酰胺的单取代配合物可以作为含有环外{PR2}单元的P5配体获得(4:R=Cy,H;5:R=Ph)。分离出这些单阴离子络合物2-5,随后的亲电子猝灭揭示了新型的中性官能化多磷络合物。这些复合物带有P5R\'R\'\'的形式链(6:R\'=tBu,R\'=Me)在1,3-双置换模式或P6R\'R\'\'R\'\'\'\'\'单位(7:R\'=Cy,R\'\'=H,R\'\'\'=Me;8:R\'=Me,R\'\'=PH,R\'\'\'=Me)在1,1,3-取代中,中间甲板由一个{Cp\'\'\'Co}和一个{Cp*Fe}片段稳定。AgBF4对2、3或5的单电子氧化可以以各种配位方式获得带有P5R中间甲板的顺磁性三层配合物(R=tBu(10),R=PPh2(12))。有趣的是,对于R=Me(11),观察到二聚化,揭示了包含独特的二氢富瓦烯型P10R2配体的抗磁性四核簇。所有络合物均通过晶体学和光谱学方法(EPR,通过DFT计算阐明了多核NMR和质谱)及其电子结构。
    The heterobimetallic triple-decker complex [(Cp*Fe)(Cp\'\'\'Co)(μ,η5  : η4 -P5 )] (1) was functionalized by main group nucleophiles and subsequently electrophilically quenched or oxidized. Reacting 1 with group 14 nucleophiles revealed different organo-substituted P5 R middle-decks depending on the steric and electronic effects of the used alkali metal organyls (2: R=tBu; 3: R=Me). Further, with group 15 nucleophiles, the first structural characterized monosubstituted complexes with phosphanides could be obtained as P5 ligands containing exocyclic {PR2 } units (4: R=Cy, H; 5: R=Ph). These monoanionic complexes 2-5 were isolated and subsequent electrophilic quenching revealed novel types of neutral functionalized polyphosphorus complexes. These complexes bear formal chains of P5 R\'R\'\' (6: R\'=tBu, R\'=Me) in a 1,3-disubstitution pattern or P6 R\'R\'\'R\'\'\' units (7: R\'=Cy, R\'\'=H, R\'\'\'=Me; 8: R\'=Me, R\'\'=Ph, R\'\'\'=Me) in a 1,1,3-substitution as middle-decks stabilized by one {Cp\'\'\'Co} and one {Cp*Fe} fragment. One-electron oxidation of 2, 3 or 5 by AgBF4 gave access to paramagnetic triple-decker complexes bearing P5 R middle-decks in various coordination fashions (R=tBu (10), R=PPh2 (12)). Interestingly, for R=Me (11), a dimerization is observed revealing a diamagnetic tetranuclear cluster containing a unique dihydrofulvalene-type P10 R2 ligand. All complexes were characterized by crystallographic and spectroscopic methods (EPR, multinuclear NMR and mass spectrometry) and their electronic structures were elucidated by DFT calculations.
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  • 文章类型: Journal Article
    致力于比较四并苯衍生物的NLO(非线性光学)响应的理论研究结果,等时,和芘报告。静态超极化率β,偶极矩μ,HOMO和LUMO轨道,并且使用CAM-B3LYP密度泛函结合cc-pVDZ基集计算它们的能隙。对位二取代的NO2-并四苯-N(CH3)2具有最高的NLO响应,这与大的分子内电荷转移有关。将乙烯基添加到对位二取代的NO2-并四苯-N(CH3)2导致NLO响应的增加。我们进一步研究了扶手椅型单壁碳纳米管内部各种推拉分子的嵌入效果。嵌入导致NLO响应增加,关键取决于客体分子的位置和/或通过供体和吸引基团对纳米管的功能化。
    Results of a theoretical study devoted to comparing NLO (non-linear optics) responses of derivatives of tetracene, isochrysene, and pyrene are reported. The static hyperpolarizability β, the dipole moment μ, the HOMO and LUMO orbitals, and their energy gap were calculated using the CAM-B3LYP density functional combined with the cc-pVDZ basis set. The para-disubstituted NO2-tetracene-N(CH3)2 has the highest NLO response, which is related to a large intramolecular charge transfer. Adding vinyl groups to the para-disubstituted NO2-tetracene-N(CH3)2 results in an increase in the NLO responses. We further investigated the effect of the intercalation of various push-pull molecules inside an armchair single-walled carbon nanotube. The intercalation leads to increased NLO responses, something that depends critically on the position of the guest molecule and/or on functionalization of the nanotube by donor and attractor groups.
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  • 文章类型: Journal Article
    基于聚酯的支架对于各种组织的再生具有研究意义。然而,需要改善支架润湿性并引入生物活性。表面改性是一种广泛研究的方法,用于改善支架性能并保持适当的整体性能。在这项研究中,比较了使用明胶固定化使聚(丙交酯-共-ε-己内酯)PLCL纤维的表面官能化的三种方法。水解,氧等离子体处理,选择氨解作为活化方法,在明胶固定化之前在表面上引入羧基(-COOH)和氨基(-NH2)官能团。共价连接明胶,选择碳二亚胺偶联用于水解和等离子体处理的材料,在氨基分解样品的情况下使用戊二醛交联。制备明胶的物理包埋和使用碳二亚胺偶联固定而没有预先活化的材料作为对照。表面上明胶量的差异,对纤维形态的影响,分子量,根据改性的类型和活化的应用参数,观察到机械性能。结果表明,水解对材料表面的影响最大,而等离子体处理和氨解对材料的整个体积有影响。尽管有这种差异,所有方法的整体机械性能都受到影响。所有材料在官能化之后是完全亲水的。对于任何样品均未发现细胞毒性。明胶固定化导致改善的L929细胞形态,对于用水解和等离子体处理活化的样品具有最佳效果。我们的研究表明,任何表面活化方法的使用都应限于最低的浓度/反应时间,以实现随后令人满意的功能化,并且该决定应基于最终支架材料必须执行的特定功能。
    Polyester-based scaffolds are of research interest for the regeneration of a wide spectrum of tissues. However, there is a need to improve scaffold wettability and introduce bioactivity. Surface modification is a widely studied approach for improving scaffold performance and maintaining appropriate bulk properties. In this study, three methods to functionalize the surface of the poly(lactide-co-ε-caprolactone) PLCL fibres using gelatin immobilisation were compared. Hydrolysis, oxygen plasma treatment, and aminolysis were chosen as activation methods to introduce carboxyl (-COOH) and amino (-NH2) functional groups on the surface before gelatin immobilisation. To covalently attach the gelatin, carbodiimide coupling was chosen for hydrolysed and plasma-treated materials, and glutaraldehyde crosslinking was used in the case of the aminolysed samples. Materials after physical entrapment of gelatin and immobilisation using carbodiimide coupling without previous activation were prepared as controls. The difference in gelatin amount on the surface, impact on the fibres morphology, molecular weight, and mechanical properties were observed depending on the type of modification and applied parameters of activation. It was shown that hydrolysis influences the surface of the material the most, whereas plasma treatment and aminolysis have an effect on the whole volume of the material. Despite this difference, bulk mechanical properties were affected for all the approaches. All materials were completely hydrophilic after functionalization. Cytotoxicity was not recognized for any of the samples. Gelatin immobilisation resulted in improved L929 cell morphology with the best effect for samples activated with hydrolysis and plasma treatment. Our study indicates that the use of any surface activation method should be limited to the lowest concentration/reaction time that enables subsequent satisfactory functionalization and the decision should be based on a specific function that the final scaffold material has to perform.
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