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Understanding the mechanisms underlying cancer cell survival is critical toward advancing drug discovery efforts in this field. Supplemental vitamins have been proposed to play a role in cancer cell metabolism because the increased supply of nutrients is thought to provide cofactors supporting the higher metabolic rate of cancer cells. Particularly, the role of thiamine (vitamin B1) in many biochemical pathways that supports cancer cell metabolism has been investigated. Consequently, the analysis of thiamine and its derivatives in a manner that reflects its dynamic response to genetic modification and pathophysiological stimuli is essential. In this work, we developed a mass spectrometry based-analytical method to track metabolites derived from stable isotope tracers for a better understanding of the metabolic fate of thiamine in cancer cells. This method used ion-pair reversed phase liquid chromatography to simultaneously quantify underivatized thiamine, thiamine monophosphate (TMP) and thiamine pyrophosphate (TPP) in cells. Hexylamine was used as an ion-pairing agent. The method was successfully validated for accuracy, precision and selectivity in accordance with U.S. FDA guidance. Furthermore, the method was then applied for the determination of thiamine and its derivatives with stable isotope labeling to explore the metabolic fate of intracellular thiamine in cancer cells. The finding shows that thiamine is rapidly converted to TPP however, the TPP does not return to thiamine. It appears that TPP may be utilized for other purposes rather than simply being an enzyme cofactor, suggesting unexplored roles for thiamine in cancer. Unlabelled Image • Hexylamine used for ion-pair chromatography and amprolium as the internal standard • Method validated following US FDA guidelines • Method applied to explore the metabolic fate of thiamine in cancer cells [ABSTRACT FROM AUTHOR]

• NiMo bimetallic nitrides catalyzed the conversion of aliphatic acyclic amides to amines. • Ni/Mo ratio influences the formation of different active phases. • 93.9 % conversion of hexanamide is achieved with 75.1 % yield to hexylamine. • Synergetic effect between Ni 2 Mo 3 N and Ni 6 Mo 6 C 1.06 promotes hexanamide conversion. Primary amines are vital building blocks in pharmaceutical and polymer industry. The heterogeneous catalytic hydrogenation of aliphatic acyclic amides to amines is rather attractive but challenging due to low reactivity of aliphatic acyclic amides, and then rarely be reported. Herein, cheap bimetallic NiMo nitride catalysts were synthesized by hydrothermal method and firstly utilized to the efficient conversion of a wide range of aliphatic acyclic amides to amines, achieving 93.9 % conversion of hexanamide and 75.1 % yield to hexylamine. Characterizations such XRD, N 2 Physical adsorption, TGA, Raman, XPS, SEM-EDX Mapping and (HR)TEM revealed that Ni 2 Mo 3 N is crucially important for the activation of hexanamide while the synergetic effect between Ni 2 Mo 3 N and Ni 6 Mo 6 C 1.06 would further promote the conversion of hexanamide, and higher TOFs (145.9 h−1) and lower Ea (29.5 kJ mol−1) are achieved. The C O bond of the amide can be activated by the surface Lewis acid site of bimetallic NiMo nitrides, while the simultaneous dissociation of H 2 to form H atoms is beneficial for hydrogenation. This catalyst is also found to be recyclable with stable catalytic performance upon consecutive runs. The present work provides a novel and unique option for the efficient conversion of aliphatic acyclic amides to amines, being a strong supplementary to those reported for the hydrogenation of cyclic-amides, secondary amides, and tertiary amides. [ABSTRACT FROM AUTHOR]

Natural clinoptilolite tuff was pre-treated and changed to micro (MCP) and nano (NCP) particles by mechanical method. Modification of MCP and NCP particles and also their Cd-exchanged forms was done by alcoholic-aquatic Hexylamine (HA) solution. The raw and modified samples were characterized by XRD, FT-IR, SEM, TEM, BET and TG. Removal of Cd(II) by the modified and unmodified samples confirmed that NCP-HA sorbent is better sorbent with respect to MCP, NCP-HA, MCP-HA, NCP-Cd-HA and MCP-Cd-HA. The modified samples showed good selectivity for cadmium among various investigated multivalent cations. Obeying the adsorption isotherms from Langmuir equation indicates the monolayer sorption of Cd(II) onto the sorbent. Fitting the adsorption kinetic in the pseudo-second-order rate equation indicates that the chemical reaction rate limiting step for the process. The negative ΔH and ΔG indicate an exothermic and spontaneous process. The negative ΔS indicates that during the adsorption of cadmium cations from solution onto the sorbent shows that total entropy of the system was decreased. [ABSTRACT FROM AUTHOR]

Hexylamine (HA) functionalized reduced graphene oxide (RGO-HA) was prepared via the modification of graphene oxide (GO) with HA, followed by reduction with hydrazine hydrate. The structure of RGO-HA was confirmed using various characterization techniques. RGO-HA was easily dispersed in several organic solvents due to its hydrophobic nature. Accordingly, RGO-HA/polyurethane (PU) composites were synthesized using different amounts of RGO-HA for their potential application in the field of barrier materials. Fourier-transform infrared spectroscopy (FTIR), wide angle X-ray diffraction (WAXS) analysis, and field emission scanning electron microscopy (FESEM) showed that RGO-HA in PU was fully exfoliated and uniformly dispersed. The hydrogen gas barrier films were prepared by spray coating of RGO-HA/PU nanocomposite solutions on nylon films. Good attachment between the nylon surface and nanocomposite was confirmed by cross sectional field emission scanning electron microscopy. The nanocomposite coated nylon film having 43.3 wt% RGO-HA exhibited an 82% decrease in the hydrogen gas transmission rate (GTR) compared to a pure nylon film. The high reduction in GTR values of the coated films may motivate to use alkyl amine-modified reduced graphene oxide and PU nanocomposite for the future development of effective barrier materials. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) were functionalized by hexylamine (HA) in a promising, cost-effective, rapid and microwave-assisted approach. In order to decrease defects and remove acid-treatment stage, functionalization of MWCNTs with HA was carried out in the presence of diazonium reaction. Surface functionality groups and morphology of chemically-functionalized MWCNTS were characterized by FTIR, Raman spectroscopy, thermogravimetric analysis (DTG), and transmission electron microscopy (TEM). To reach a promising dispersibility in oil media, MWCNTs were functionalized with HA. While the cylindrical structures of MWCNTs were remained reasonably intact, characterization results consistently confirmed the sidewall-functionalization of MWCNTs with HA functionalities. Then, HA-treated MWCNTs-based turbine oil nanofluids (HA-MWCNTs/TO) with different volume fractions were synthesized and employed to be investigated in terms of heat transfer potential. Convective heat transfer coefficient of HA-MWCNTs/TO as a positive parameter and pressure drop as a negative factor were investigated for various volume fractions. While results suggested a weak increase in the pressure drop by MWCNTs loading into the TO, lack of acidic agents, the performance index higher than 1 and a significant increase in the convective heat transfer open a new gateway for introducing this economical product for industrial applications in turbines and can be a capable alternative for conventional TO. [ABSTRACT FROM AUTHOR]

In this paper the influence of hexylamine, as an example of a short chain alkyl amine, on the flotation behaviour and interfacial properties of quartz was investigated. It was shown that hexylamine enhanced the flotation performance of quartz regardless of the type of flotation device. The foaming properties of hexylamine and its adsorption at the liquid/gas interface showed that hexylamine in the flotation process plays a role of a frother. It was also shown that hexylamine “uncovers” the natural hydrophobicity of quartz, which is sufficient to be attached to the liquid/gas interface. [ABSTRACT FROM AUTHOR]

A novel system for measuring the crosslink densities of mono-, di- and polysulfides of a filled rubber vulcanizate was developed. The system included pre-swelling, cleavage of sulfur crosslinks by a chemical probe using thiol/ n -hexylamine instead of thiol/piperidine, and two step swelling. A sample cage made of stainless steel mesh was used to measure multiple samples at the same time and to reduce experimental errors. The organic materials-extracted sample was pre-swollen in toluene to introduce the probe chemicals more rapidly and homogeneously into the whole network. Polysulfidic crosslinkages were cleaved by a chemical probe of propane-2-thiol/ n -hexylamine in toluene, while di- and polysulfidic crosslinkages were dissociated by a chemical probe of n -hexanethiol/ n -hexylamine in toluene. The experimental errors were lower than 2%. By using cubic apparent crosslink density, fractions of the crosslink types of an unknown rubber vulcanizate could be estimated even although the filler content and rubber composition are not analyzed. [ABSTRACT FROM AUTHOR]

Abstract: The knowledge regarding the synthesis of new organic derivatives with controlled morphology on the basis of kaolin group minerals is increasing. Apart from kaolinite, new materials were obtained using halloysite. However, organic derivatives of dickite are not well known. In this study dickite was tested in a grafting reaction with methanol and also an intercalation of hexylamine was performed. As a precursor dickite–dimethyl sulfoxide complex was used. The results confirmed the possibility to modify the interlayer octahedral surface of dickite with methoxyl groups by low temperature grafting with methanol. This methoxy-modified mineral was intercalated with hexylamine. The approximate model of the new intercalate was proposed on the basis of XRD and IR data. Deintercalation of the hexylamine led to a delamination of dickite particles and subsequent formation of mineral nanotubes by rolling of the dickite layers. As a consequence, the measured specific surface area and total pore volume increased significantly in comparison to the raw dickite. [Copyright &y& Elsevier]

Abstract: Precursor-type Cu inks were formulated by mixing copper (II) formate and hexylamine. The lowest electrical resistivity obtained in Cu films made from these inks was 5.2μΩ·cm. The Cu concentrations in the inks influenced the impurity content after annealing and the microstructure (specifically, the porosity). Inks with a higher volume of hexylamine had a narrower size distribution of Cu particles, so they formed denser films. However, a large volume of hexylamine could not be fully vaporized during a limited annealing time and reacted with formate, creating impurities having boiling temperatures higher than that of hexylamine. Therefore, the Cu concentration governed two factors, porosity and impurity content, which ultimately determined the electrical resistivity of the films. These findings are expected to facilitate the development of copper-based metallic inks for printed electronics. [Copyright &y& Elsevier]

Abstract: Stable foams have been generated in low concentration aqueous dispersions of hexylamine-modified Laponite particles. The particles are of primary size 30nm, modified with hexylamine molecules to render them partially hydrophobic or moderate flocculants. Infrared adsorption spectra and zeta potential measurements confirm the adsorption of hexylamine molecules on the Laponite particles. The foamability, drainage behavior and microstructure of wet foams were studied in terms of their dependence on the content of Laponite particles and the concentration of hexylamine. Laser-induced confocal microscopy observations confirm that stable bubbles appear to be surrounded by a thin layer of hexylamine-modified Laponite particles, which is crucial to the stability of foams. The interfacial rheology of the same systems has been also investigated by measuring the dilational viscoelasticity as a function of hexylamine concentrations. The adsorption of particles at the air–water interface has the effect of increasing dilational surface elasticity, indicating that the gel-like layer at the interface inhibits foam drainage and bubble coalescence. [Copyright &y& Elsevier]

Abstract: Sol–gel hydrolysis reactions of titanium(IV) isopropoxide and chromium (III) acetate hydroxide in the presence or absence of propanol, using the following amines as structure directing agents; N-hexylamine, N-methylhexylamine, and N-propylbutylamine, yielded microporous mixed metal oxides with the presence of pores largely in the 10–20Å region, and surface areas that vary from 564m2/g when N-hexylamine is employed as pore directing template to 494m2/g when N-propylbutyl amine is employed as template. The maxima in pore size distribution increases with increase in steric crowding around the nitrogen in the alkyl amine. In addition, the nitrogen adsorption–desorption isotherm shifted from Type 1 isotherm when N-hexylamine is used as templating agent to Type 4 isotherm in N-propylbutylamine. [Copyright &y& Elsevier]

• Weight loss, PDP, EIS, MRM, SEM, LAI, FAI and DFT studies were performed. • Effect of molecular structure i.e., acyclic and cyclic CI was investigated. • HA (acyclic) was proved better corrosion inhibitor than CHA (cyclic). • CHA and HA shows 81.06% and 85.13% PCIE for CS in 2 N HCl at 25°C. • BOD and COD were found in acceptable limit. To understand the effect of molecular structure (cyclic and acyclic) on the corrosion inhibition properties, cyclohexylamine (CHA) and hexyl amine (HA) were investigated as corrosion inhibitors for Carbon Steel (CS) in 2 N hydrochloric acid at 25, 30, and 35°C. Experimental methods like gravimetric, polarization and impedance spectroscopy were used. Different kinetic and thermochemical investigations were made by density functional theory. The IR absorption spectra (theoretical and experimental) were obtained after performing frequency operation on geometry optimized structures of CHA and HA. The type of inhibition provided by CHA and HA was examined by computational and experimental techniques. The adsorption study (theoretical and experimental) shows that the HA molecules adsorb uniformly on CS in a linear chain by forming a stable coordinate covalent bond between Fe (110) surface and N atoms. CHA and HA showed 81.06% and 85.13% corrosion inhibition efficiency, respectively. Linear chain acyclic hydrocarbon i.e., HA was proved to be a better inhibitor than cyclic hydrocarbon, CHA having almost similar molecular formula. The Biochemical and chemical oxygen demand of wastewater was found within the acceptable level. [Display omitted] [ABSTRACT FROM AUTHOR]