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Supercritical Fluid Chromatography (SFC-UV) employing a carbon dioxide (CO 2) and 10 mM ammonium acetate in MeOH-water (95:5 v/v) gradient provides a rapid analysis (t G

Fluorinated fentanyl regioisomers have become increasingly common in forensic casework. This study reports the synthesis of eight fluorinated fentanyl derivatives as pure reference materials and their complete NMR, infrared and mass spectral characterisation. Presumptive colour tests and TLC results are presented as an initial screening method for these compounds. The fully validated GC–MS method (employing SIM mode) allows the quantification of the target analytes (LOD = 9 – 20 ng/mL, LOQ = 31 – 67 ng/mL), fentanyl, heroin, acetaminophen and caffeine, within 13 minutes. In most cases, the regioisomeric fluorofentanyls were resolved from each other except for the 3’- and 4’-fluorinated derivatives (5b and 5c). To achieve full separation, an orthogonal benchtop 19F NMR method allows the identification and quantification of target analogues (LOD = 74 – 400 μg/mL, LOQ = 290 – 1340 μg/mL). The 19F NMR method allows the detection of fluorinated fentanyl analogues at a low concentration (2.4% w/w) in heroin.

Recreational MDMA use is a worldwide problem. Tablet dosage varies, thus entailing a requirement for quantitative analysis. The quantification of MDMA in tablets using benchtop 1H NMR spectroscopy via either linear regression (‘manual’ method) or partial least square regression (‘automated’ method) approaches are reported, without the need for an internal standard, and compared against contemporaneously obtained GC–MS data. Twenty samples were evaluated of which 15 were proven to contain MDMA, via qualitative NMR (hit score ≥ 0.97) and GC–MS (Rt = 5.6 min) analysis. Quantitative NMR analysis showed that the mean value of MDMA content was 42.6% w/w by the manual method and 45.9% w/w by the automated method. The mean value obtained from GC analysis was 44.0% w/w. A substantial proportion (n = 9) of the tablets tested possessed > 190 mg of MDMA (range 133–223 mg, average of all techniques’ calculations for each tablet). This value is higher than the reported average MDMA content of tablets by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), which was ca. 125 mg of MDMA per tablet in 2016.

Moringa oleifera (Lam.), an edible plant found to have high nutritional value, has recently attracted intense research interest due to its high glucosinolate (GS) content giving the plant its chemoprotective attribute. The plant grows well in dry environments, but is also found in moist tropical or subtropical climates. Thus, it is widely cultivated in Asia, Africa, South and North America. However, the plant’s leaf compartment harvested for food, and post-harvest technologies used to process the leaves in developing countries where long transportation routes and high fluctuating temperatures are inevitable, can influence the stability of GS contents. Therefore, the present study investigated the influence of different harvesting techniques and commonly used traditional drying-methods on the stability of GS in M. oleifera leaves during post-harvest. Leaves were subjected to either of the following drying methods: sun-, oven-, solar- and shade-drying and GS analysis was conducted. Results revealed that sun- and oven-drying of M. oleifera leaves retained significantly higher GS contents (101.54 and 84.67 µmol/g dw, respectively) compared to solar- and shade-drying (64.46 and 45.30 µmol/g dw, respectively). To test for effects of harvest technique on GS contents and stability of GS during post-harvest, two leaf compartments, i.e. pinnae and leaflets were harvested separately. Leaf compartments were subjected to either oven- or freeze-drying methods. The samples from each drying method were divided into two portions, where GS were immediately analyzed in one portion and the other analyzed after one month storage at ambient temperature. Results showed that factors such as harvest technique (harvesting pinnae or leaflets of the plant) and the storage time influences GS content of M. oleifera leaves significantly.

Synthetic cannabinoid receptor agonists (SCRAs) are a continually evolving family of illicit drugs, with novel analogues frequently being detected. This paper reports the detection of a new N-hexyl-1H-indazole derivative, ADB-HINACA, within a herbal sample seized by law enforcement for the first time in the United Kingdom. The identity of the compound was confirmed via the synthesis of a pure ADB-HINACA reference standard and direct spectral comparison by 1H NMR and GC-EI-MS analysis. A full analytical profiling of ADB-HINACA by nuclear magnetic resonance (NMR), attenuated total reflection Fourier-transform infrared (FTIR) spectroscopy and gas chromatography-electron ionisation-mass spectrometry (GC-EI-MS) is reported and shows good concordance between the seized sample and the reference standard. A validated GC-EI-MS method for the routine quantification of the cannabinoid in seized samples (LOD: 1.7 μg/mL, LOQ: 5.8 μg/mL) was also developed and using this method, the seized herbal sample was determined to contain 4.9% w/w ADB-HINACA.

A magnetic method for the in-situ inspection of the combined effects of both, clamping force (CF) and the distribution of the surface residual stress (RS) on a face milled workpiece are presented. FE simulations have been conducted and evaluated, illustrating the impact of clamping on the workpiece surface deflection and thus, the machining accuracy. Furthermore, magnetic Barkhausen noise (MBN) signals were acquired on a hot-work tool steel workpiece after three different milling procedures: Face milling, one pass of micro-milling and 38 passes of micro-milling. Finally, the MBN signal on the unclamped workpiece was obtained. The MBN signal energy MBNenergy presented the highest values with the probe oriented in the pick (clamping) direction for all stages of milling process where the CF was applied. After unclamping the workpiece, the higher value of the MBNenergy was obtained with the probe oriented in feed direction of the milling processes revealing the true effect of the RS. These results were in agreement with the literature and confirmed by numerical simulations and X-ray diffraction based residual stress measurements.

Side-bridged cyclam transition metal complexes (M = Ni(II), Cu(II) and Zn(II)) bearing a phenolic ether or phenolate pendent arm have been synthesised. For [NiL1]+ and [CuL1]+, evidence for a phenoxyl radical was obtained (quasi reversible peak at +0.74 V and +0.48 V respectively), as well as oxidation of OH, due to protonation of the phenolate, at ∼+1.24 V. The phenoxyl radical in [Ni(L1)]2+ is harder to oxidise by 0.26 V compared with the corresponding Cu(II) complex. UV–Vis data for [Ni(L1)]2+ suggests that the Ni(II) ion may be 4 or 6 coordinate whereas the Cu(II) ion in [Cu(L1)]2+ is five coordinate. The Ni(II) ion in the crystal structure of [Ni(L2)][(ClO4)2] possesses a distorted square-planar geometry in which the phenolic ether pendent arm is not involved in the coordination sphere. The cyclam ligand in this complex adopts a trans-II configuration.

The emergence of a wide variety of fentanyl analogues has become a problem for the identification of seized drug samples. While chemical databases are largely reactive to the emergence of new analogues, efforts should focus on the development of predictive models which can discern how new analogues differ from the parent drug. Principal component analysis (PCA) was performed on mass spectral data from 54 fentanyl analogues. Hierarchical clustering was used to group these analogues into meaningful classes. The model was able to classify 67 analogues not previously included in the model with high accuracy, based on the nature and position of the chemical modification.

Determining plant reactions to atmospheric pollutants is important in predicting and planning for new horticultural production management programs and challenges in the future. A high level of ozone in the troposphere is considered the most phototoxic air pollutant, and has strong oxidative potential. This study aimed to provide understanding on the role of ozone stress on early vegetative growth stage Pak-Choi (Brassica campestris L. ssp. chinensis). An experiment was conducted within airtight bio-chambers under 150 ppb ozone concentration with different exposure durations: control, 1 h/day and 4 h/day. The leaf area was not affected by ozone treatment, but the dry matter correlated negatively with increasing ozone exposure durations. In photopigments, the lutein, lycopene and chlorophylls were increased at 1 h/day exposure, however, total carotenoids and β-carotene were not affected. However, for the 4 h/day exposure condition, all photopigment contents were significantly decreased in comparison to the 1 h/day exposure. The total aliphatic and total glucosinolate (GLS) were significantly increased at 1 h/day exposure, and then significantly decreased at 4 h/day exposure. However, the total indole and aromatic GLS were significantly increased after 4 h/day exposure. Therefore, these results provide evidence about the impact of ozone stress on the specific secondary plant metabolites of Pak-Choi and this needs to be taken in account when selecting urban production sites for vegetables.

Hyperpolarization produces nuclear spin polarization that is several orders of magnitude larger than that achieved at thermal equilibrium thus providing extraordinary contrast and sensitivity. As a parahydrogen induced polarization (PHIP) technique that does not require chemical modification of the substrate to polarize, Signal Amplification by Reversible Exchange (SABRE) has attracted a lot of attention. Using a prototype parahydrogen polarizer, we polarize two drugs used in the treatment of tuberculosis, namely pyrazinamide and isoniazid. We examine this approach in four solvents, methanol-d4, methanol, ethanol and DMSO and optimize the polarization transfer magnetic field strength, the temperature as well as intensity and duration of hydrogen bubbling to achieve the best overall signal enhancement and hence hyperpolarization level.

In the milling process of complex workpiece shapes the feed rate normally becomes instable due to the high degree of surface curvature that requires high acceleration and deceleration of the interpolated axes. This condition impacts on process time and on the surface accuracy regarding the manufactured part form and texture. The challenge to simulate the real machine and control behavior requires accurate models with a set of experiments to tune and dimension the model to the respective machine tool. The aim is to improve the HSC milling process of complex surfaces before removing any material. In this paper experiments show that the surface form accuracy and texture can be optimized through an automatic feed rate smoothing of the finishing operation directly on the machine tool. The axis positions and spindle speeds monitored through the open CNC are used as input for a geometric cutting simulation, thus enabling to predict and optimize the surface quality.

Glucosinolates are secondary plant metabolites occurring in Brassica vegetables. Food processing significantly reduces glucosinolate content, among other things due to thermal degradation. As there is only little information about thermal glucosinolate breakdown, the influence of the chemical structure as well as the influence of different pH to thermal degradation of individual glucosinolates was studied by analysing desulphoglucosinolates with HPLC-DAD. Thermal degradation was forced by heating broccoli sprouts at 130 °C in dry medium, whereas the influence of the pH was studied by cooking at 100 °C in aqueous medium . Within each group of glucosinolates differences in thermal degradation were revealed. Within the sulphur containing aliphatic glucosinolates the oxidative state of the sulphur atom as well as the side chain length influenced the reactivity. Among the indole glucosinolates great differences in stability were observed. A hydroxyl function in the side chain generally seems to destabilise glucosinolates. Glucosinolates were most stable towards thermal treatment in neutral and slightly acidic medium, whereas they degraded more rapidly in basic medium.

In this work we examined the chemical elicitors streptomycin, activated charcoal and ethephon, and the elicitor-like effects of high hydrostatic pressure (HP) on plant cells with respect to the induction of plant defense responses and secondary metabolites production. The effects of HP and elicitors on growth and secondary metabolism, particularly anthocyanins and phenolic acids synthesis, accumulation in cells and exudation into the cultivation medium were investigated by using suspension culture of Vitis vinifera L. cv. Gamay Freaux as a model system. Anthocyanins were measured by spectrophotometer and phenolic acids were determined by HPLC. The compounds were identified by LC–MS and NMR. After the treatments with HP and elicitors, the concentrations of phenolic acids in culture medium were higher than in the control, without loss of biomass, while the production of anthocyanins from cells was not affected. The combination of HP and ethephon treatment improved secondary metabolites formation. Production levels of extracellular phenolic acids and 3-O-glucosyl-resveratrol were increased by HP and ethephon treatments. The results show that HP induced a defense response of plant cells and may have altered the cell/membrane's properties.

We present the first modern description of corals, brachiopods and bivalves from the Antalo Limestone in the Mekele Outlier of northern Ethiopia. This fauna is largely of Oxfordian age and lived in shallow subtidal environments and in small patch reefs. In combining our new data with fossil occurrence data from the Paleobiology Database, we conducted multidimensional scaling analyses to assess biogeographic patterns and the delineation of the Ethiopian Province for the Callovian to Kimmeridgian stages. Results suggest that an Ethiopian Province is indeed evident for our focal groups, but this is more confined than traditionally assumed. The so defined Ethiopian Province includes Tunisia, the Levant, Arabia and much of East Africa, but excludes Tanzania and India. The special status of India and Tanzania is perhaps due to latitudinal gradients in faunal composition.

The synthesis of 1-(4-nitrobenzyl)-2-chloromethyl benzimidazole, which undergoes a nucleophilic substitution with pyridine in the absence of additional base, is reported. The key steps are the reaction of 1,2-phenylenediamine to give exclusively the mono-substituted product and the avoidance of minor by-products via the use of glycolic acid for the cyclisation step. The X-ray structures of 1-(4-nitrobenzyl)-2-chloromethyl benzimidazolium chloride and 1-[1-(4-nitrobenzyl)benzimidazol-2-ylmethyl]pyridinium chloride are presented.

Macrocyclic chelators can form highly stable complexes with transition metals and lanthanides. In this review, the recent advances towards biomedical applications of macrocyclic complexes are outlined. The use of such complexes in imaging as MRI contrast agents, radiopharmaceuticals and luminescent probes is discussed. The considerable scope for future development of novel metal based therapeutics based on protein binding, targeting of radioisotopes or dual function agents is also highlighted.

Treatment of 5,10,15,20-tetra(pentafluorophenyl) porphyrins with polyethylene glycol (PEG) halides and sodium sulfide is a mild and efficient route to water-soluble PEG substituted porphyrins. The method has been used to access a series of free-base and metallated PEG porphyrins, which have been investigated for photodynamic activity against Human Caucasian colon adenocarcinoma (Caco2) cells. Toxicity, in the presence and absence of light, is shown to be affected by the length of the PEG chain, nature of coordinated metal and axial ligand.

The complex rheological behaviour of suspensions is very strongly affected by the details of the microstructure and the interparticle forces by which it is controlled. The difficulties involved in characterizing the microstructure, in particular during flow, caused the development of suspension rheology to lag behind that of polymer rheology. Progress in theory, experiments and simulation is rapidly changing the picture, providing opportunities for further significant developments. Possible evolutions in six areas of suspension rheology are discussed here.

Glucotropaeolin and total phenolic concentrations were assessed in three different organs (inflorescences, leaves, unripe seeds) of nasturtium ( Tropaeolum majus L.), which are consumed as herbal plant products, in order to determine the effect of short-term and moderate UV-B exposure as targeted postharvest stress treatment on the secondary plant metabolism. For this purpose, nasturtium plants were subjected to two UV-B radiation levels: 0.075 and 0.15 W h m − 2 . The results clearly demonstrate that the plant response to short-term and moderate UV-B exposure is organ-, plant tissue age-, and phytochemical-specific and that these factors influence a change of secondary metabolism as revealed by the different phytochemical concentration levels elicited. Industrial relevance In food processing UV treatment is mainly attributed to disinfection. This study examined the feasibility of short-term and moderate UV-B application as emerging technology for enhancing health-promoting phytochemicals in freshly consumed plant products (inflorescences, leaves, unripe seeds) demonstrated by the herbal plant nasturtium. Optimizing phytochemical concentration by targeted postharvest UV-B applications will add health value and subsequently generate new opportunities for growers and processors by achieving the health-oriented food market.

The flow-induced orientation of spheroidal particles in viscoelastic fluids is studied by means of rheo-optical methods and flow microscopy. Using suitable model systems a wide range of rotational Peclet and Weissenberg numbers have been covered, providing a systematic and global picture of the various orientational transitions. The effects of particle size and aspect ratio have been considered separately. Increasing the shear rate gradually causes first the well-known change from a random orientation to spinning in Jeffery orbits. Upon further increasing both the Peclet and Weissenberg numbers, the period of rotation becomes larger. At this stage the orbits start to drift slowly toward a ‘log-rolling’ state, which leads to an orientation distribution function that is narrowly peaked around the vorticity axis. For the fluids tested here, the orbit drift rates are proportional to the shear rate. At still higher elasticities, the particles are observed to reorient again in the flow direction, with the notable exception of suspensions in Boger fluids. Some of the experimentally observed features are qualitatively in line with the results of a theory for slender bodies in second order fluids, despite both relatively small aspect ratios and a more complex rheological behavior of the suspending media. An effect of absolute particle size is also noted which might indicate interference from Brownian motion, as suggested earlier. With suitable flow histories bimodal flow-vorticity orientation distributions can be generated. Finally, specific flow-induced alignment and aggregation are observed, they are more difficult to generate than in suspensions with spheres.

A general structural kinetics model is presented to describe the flow behaviour of thixotropic systems based on inelastic suspending media. The total stress is divided in structure-dependent elastic and viscous contributions. The kinetic equation for the structure parameter takes into account the effect of shear on structure breakdown and build-up, as well as the effect of Brownian motion on build-up. The relaxation and deformation of the flocs is also included. Both the kinetic and the relaxation equations contain a distribution of time constants. The predictions of this model, as well as those of two representative models from the literature, are compared with experimental data using an objective method for parameter estimation. Model validation is based on stress transients resulting from sudden changes in shear rate, including both structure build-up and breakdown. The predictions of the viscous and elastic components are evaluated separately using stress jump experiments with steady and non-steady state starting conditions.

A number of models are available to describe the rheological behaviour of associative polymers. Model evaluation has most often been limited to the linear properties and to a qualitative prediction of the characteristic shear thickening at intermediate shear rates. Several other nonlinear features of associative behaviour have, however, been identified. These include failure of the Cox–Merz analogy and an unusual response in nonlinear stress relaxation, large amplitude oscillatory flow and in superposition flows. Here, experimental results for such experiments are compared with the predictions of a transient network model, i.e. the Vaccaro–Marrucci model [J. Non-Newtonian Fluid Mech. 92 (2000) 261], which has only a single adjustable parameter to describe nonlinear behaviour. It is shown that the various nonlinearities are well predicted qualitatively. The only deviation is a substantial overprediction of the critical strain or strain rate for the onset of these nonlinearities. The effect of changing the value of the model parameters and of relaxing the model assumptions on the predictions is investigated. The results suggest that the presence of a small number of highly stretched chains could be responsible for the observed deviation from the experimental data.

(PPE/PS)/PA6 and PS/PA6 blends were prepared by means of melt-extrusion. They were compatibilized using the reactive styrene-maleic anhydride copolymer with 2 wt% maleic anhydride (SMA2). The effect of compatibilization on the phase inversion and the stability of the resulting co-continuous blend structures were investigated using scanning electron microscopy, dissolution and extraction experiments. The onset of co-continuity shifted towards lower PA6 concentrations according to the change in blend viscosity ratio. The melting order of the components inside the extruder could result in a change in the observed co-continuity interval in slowly developing phase morphologies. The unmodified co-continuous blends were not stable and did break-up into a droplet/matrix type of morphology upon annealing in the melt depending on the blend composition. Although the stability of the threads during annealing improved upon compatibilization because of the lower resulting interfacial tension, the decreased possibility for recombination and coalescence during flow reduced the co-continuous region for the compatibilized blends. It is proposed that a dynamic equilibrium between break-up and recombination phenomena after the initial network formation is necessary to maintain the network structure.

Particles suspended in viscoelastic media are known to develop string-like structures when being sheared at sufficiently high shear rates. The occurrence of these strings has been attributed to normal stress effects, and it has been suggested that a critical Weissenberg number of 10 governs their appearance. This assumption is tested here, using suspensions of monodisperse polystyrene spheres. The level of viscosity and elasticity, as well as the degree of shear thinning of the suspending fluid, have been varied over a wide range of values. The critical Weissenberg number for the onset of string formation, as detected by microscopy, was not constant but ranged from 0.5 to 16.5 in contrast with literature results. Suspensions in highly elastic Boger fluids did not display any alignment at all, even at Weissenberg numbers as high as 260. Small angle light scattering (SALS) was used to calculate an alignment factor. It provides an objective and quantitative measure for the degree of alignment of the particles. It also makes it possible, in some cases, to determine precisely the interparticle spacing in the strings. The kinetics of string formation can be studied as well, they seem to be strain-controlled. SALS experiments with different gap spacings have been used to demonstrate that the string formation occurs in the bulk of the liquid rather than at the walls of the cell.

For the first time, a microsporidian infection was observed in the pest species Hellula undalis (Lepidoptera: Pyralidae) in crucifer fields in Nueva–Ecija, Philippines. Because H. undalis is difficult to control by chemical insecticides and microbiological control techniques have not been established, we investigated the biology, the pathogenicity and transmission of this pathogen found in H. undalis. An average of 16% of larvae obtained from crucifer fields in Nueva–Ecija displayed microsporidian infections and 75% of infected H. undalis died during larval development. Histopathological studies revealed that the infection is initiated in the midgut and then spreads to all organs. The microsporidium has two different sporulation sequences: a disporoblastic development producing binucleate free mature spores and an octosporoblastic development forming eight uninucleate spores. These two discrete life cycles imply its taxonomic assignment to the genus Vairimorpha. The size of the binucleate, diplokaryotic spores as measured on Giemsa-stained smears was 3.56±0.29 μm in length and 2.18±0.21 μm in width, whereas the uninucleate octospores measured 2.44±0.20×1.64±0.14 μm . The microsporidium was orally and probably also transovarially transmitted. Laboratory infection tests by feeding spores on artificial diet to 3rd instars resulted in 100% infection with a final mortality of 80%. Most larvae died during larval development and 40% of them died 3 days after spore ingestion. This microsporidium shows potential for microbiological pest management.

Two new compounds were synthesized by heating mixtures of the elements at 975–1025 K and characterized by single-crystal X-ray methods. CaZn 2 Si 2 ( a =4.173(2) A, c =10.576(5) A) and EuZn 2 Ge 2 ( a =4.348(2) A, c =10.589(9) A) crystallize in the ThCr 2 Si 2 -type structure (space group I4/ mmm ; Z =2). Magnetic susceptibility measurements of EuZn 2 Ge 2 show Curie–Weiss behavior with a magnetic moment of 7.85(5) μ B /Eu and a paramagnetic Curie temperature of 10(1) K. EuZn 2 Ge 2 orders antiferromagnetically at T N =10.0(5) K and undergoes a metamagnetic transition at a low critical field of about 0.3(2) T. The saturation magnetization at 2 K and 5.5 T is 6.60(5) μ B /Eu. 151 Eu Mossbauer spectroscopic experiments show one signal at 78 K at an isomer shift of −11.4(1) mm/s and a line width of 2.7(1) mm/s compatible with divalent europium. At 4.2 K full magnetic hyperfine field splitting with a field of 26.4(4) T is detected. The already known compounds Ca M 2 Ge 2 ( M : Mn–Zn) also crystallize in the ThCr 2 Si 2 -type structure. Their M Ge 4 tetrahedra are strongly distorted with M =Ni and nearly undistorted with M =Mn or Zn. According to LMTO electronic band structure calculations, the distortion is driven by a charge transfer from M –Ge antibonding to bonding levels.