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We present a straightforward, catalyst-free approach to the transesterification of vegetable oils, converting them into high-value biodiesel fatty acid methyl esters (FAMEs). Our method utilizes both commercial waste oils and virgin cooking oils, employing sodium tetramethoxyborate [NaB(OMe)4] derived from the reaction of sodium borohydride (NaBH4) with methanol (MeOH). NaB(OMe)4can also be produced using the inexpensive reagents trimethoxyborate [B(OMe)3] and NaOMe in methanol and was also successful at producing FAMEs. Notably, our process avoids the use of currently employed hydroxide bases, thereby averting the production of soapy diesel and eliminating the necessity for the removal of water from the reaction mixture and conversion of soapy impurities into FAMEs. Furthermore, the byproduct glycerol-boron compounds form a solid and facilitate the isolation of the biodiesel by simple decantation. Transesterification reactions were successful using cheap, abundant waste cooking oil from a major fast-food chain, as well as soybean oil, corn oil, olive oil, and animal fat, achieving an average yield of 85% for reactions performed at 80 °C for 1 h. Characterization through 1H and 11B NMR underscores the efficacy of the process and quality of the obtained biodiesel. Our method was extended to the synthesis of ethyl, propyl, and butyl fatty acid esters. This was achieved by introducing used cooking oil to NaB(OEt)4, NaB(OPr)4, and NaB(OBu)4, formed by reactions of NaBH4with EtOH, PrOH, and BuOH, respectively.

We investigate the synthesis of coordination polymers (CPs) comprising silver cations, 4,4′-bipyridine and the charge-balancing perhalogenated acetate anions trifluoroacetate (CF3COO–), trichloroacetate (CCl3COO–), tribromoacetate (CBr3COO–) or triiodoacetate (CI3COO–). The syntheses involved anion exchange using the starting CP silver 4,4′-bipyridine acetate. Multianalytical characterization was conducted using powder X-ray diffraction, single crystal X-ray diffraction, optical microscopy and thermogravimetric analysis. Our findings revealed that CPs were formed with CF3COO–or CCl3COO–as the charge-balancing anion and exhibited notable stability. In contrast, reactions with CBr3COO–and CI3COO–showed that the starting anion undergoes decomposition to bromide, iodide or triiodide before being incorporated into the resulting material. This study sheds light on the interactions between perhalogenated anions and CPs and the potential for the use of CPs in the removal of perhalogenated “forever chemicals.”

Pertechnetate, the most stable form of the radionuclide 99Tc in aerobic aqueous systems, is a hazardous anion present in nuclear waste. Its high mobility in water makes the remediation of the anion challenging. In the past decade, significant effort has been placed into finding materials capable of adsorbing this species. Here, we present the synthesis and high-resolution crystal structure of the coordination polymer [Ag(2,4′-bipyridine)]NO3, which is capable of sequestering perrhenate─a pertechnetate surrogate─through anion exchange to form another new coordination polymer, [Ag(2,4′-bipyridine)]ReO4. Both the beginning and end structures were solved by single-crystal X-ray diffraction and the adsorption reaction was monitored through inductively coupled plasma-optical emission spectroscopy and UV–vis spectroscopy. The exchange reaction follows a pseudo-second-order mechanism and the maximum adsorption capacity is 764 mg ReO4/g [Ag(2,4′-bipyridine)]NO3, one of the highest recorded for a coordination polymer or metal–organic framework. A solvent-mediated recrystallization mechanism was determined by monitoring the ion-exchange reaction by scanning electron microscopy–energy-dispersive spectroscopy and powder X-ray diffraction.

Metal halide perovskites, such as methylammonium lead bromide, have recently attracted considerable attention due to their interesting and useful photoelectric properties. Here, two types of methylammonium lead bromide magic-sized clusters (MSCs), passivated with oleylamine and oleic acid, were synthesized using ligand-assisted reprecipitation (LARP) and heated LARP (HLARP) methods. The optical properties of these MSCs were characterized using UV–vis electronic absorption and photoluminescence (PL) spectroscopies. The HLARP synthesis resulted in a two-fold increase in the PL quantum yield of the MSCs to 76%. The stability of the MSCs was tested using time-dependent PL spectroscopy. LARP MSCs in solution degraded completely after 14 days under ambient conditions, while HLARP MSCs lasted for 26 days. To stabilize them, the MSCs were added to a non-coordinating matrix, paraffin. Both MSCs showed significantly improved resistance to water with the addition of paraffin. Solid LARP MSCs lost all luminescence with and without the addition of paraffin by about 3 h. Solid HLARP MSCs without paraffin started to aggregate after 3 h, but paraffin stabilized HLARP MSC films were stable for 8 days. This improved stability in solid state form allowed for accurate, nonaggregated analysis using Raman spectroscopy, X-ray diffraction, and transmission electron microscopy. Raman spectroscopy revealed that the HLARP MSCs show an additional peak at 147 cm–1compared to LARP MSCs, which is attributed to methylammonium. X-ray diffraction and transmission electron microscopy confirm that MSCs have a quasi-crystalline orthorhombic structure.

We report the structures of six anionic, isomorphous metal–organic frameworks [Ln(bpdc)2–][NH2(CH3)2+], where Ln = La, Ce, Nd, Eu, Gd, Er, and bpdc2–= biphenyl-4,4′-dicarboxylate = –O2C(C6H4)2CO2–. The Ln(III) metal centers exhibit eight-coordinate binding to six different bpdc2–ligands (four of which are μ-2 bridging and two are bidentate) and the framework is charge-balanced by a dimethylammonium cation. The materials all possess the same 3D structure and crystallize in the orthorhombic space group Pbcn. All exhibit thermal stability up to ca. 300 °C and decompose to Ln2O3after 800 °C. The Eu-based structure exhibits strong fluorescence in the 612–620 nm range. These materials significantly expand the known chemistry and luminescence of the less studied f-block metal–organic frameworks.

We report the first example of linker modification for an N-donor Ag-based cationic material while maintaining and in some cases increasing the anion exchange capacity. Cationic silver(I) pyrazine nitrate selectively traps harmful oxo-anions from water such as permanganate, perrhenate and a variety of α,ω-alkanedicarboxylates. We chose these anions as initial examples of exchange for potential water purification. The host–guest interaction between the cationic layers of π-stacked silver pyrazine polymers and the incoming/outgoing interlamellar anions allows for the exchange. The exchange capacity over 24 h reached 435 and 818 mg/g for permanganate and perrhenate, respectively, a record for a crystalline metal–organic material and over five times the exchange capacity compared to commercial resin. The material also undergoes organic exchange as an analog for pharmaceutical waste, some of which have a carboxylate functionality at the neutral pH range typical of natural water sources. Both the as-synthesized and exchanged materials are characterized by a variety of analytical techniques.

An in-depth study of the class of cationic materials [Ag(4,4′-bipy)+][X–] (where X–= CH3CO2–, NO3–, BF4–, ClO4–, and MnO4–) has led to key insights on the relationship between anion hydration energy, material structure, solubility, and stability. Since these materials show promise for their potential as water remediation tools, understanding their properties in detail is of significant importance. The structure of the starting and ending materials is the main driving force behind the resultant stability and solubility and can be successfully used to predict the ion exchange capabilities. The solubility trend was determined to be, from most soluble to least soluble, X–= CH3CO2–> NO3–∼ BF4–> ClO4–> MnO4–. Kinetics and thermal stability also follow predictable trends but involve additional factors. For instance, the kinetics of NO3–to MnO4–exchange was much slower than expected based on that seen for NO3–to ClO4–. Powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the materials. Solubility was determined by inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis. Ion exchange was analyzed with ion chromatography (IC) and ultraviolet–visible spectroscopy (UV–vis), and thermal stability was determined with thermogravimetric analysis (TGA).

We present the rapid synthesis of a series of metal–organic framework (MOF) thin films on indium tin oxide (ITO) glass. ITO was first electrodeposited with either copper or zinc microcrystalline films (Cu-ITO and Zn-ITO, respectively) from simple aqueous/ethanol salt solutions. These metallic deposits served as the metal cation source during their partial anodic dissolution and the initial nucleation sites during electrochemical MOF (EMOF) film growth. Four different EMOF films were prepared by this method. HKUST-1 and the two-dimensional (2D) cationic framework [Cu(C10H8N2)2+]Br2(CBBr) were each grown on Cu-ITO. Zn6(OH)3(BTC)3(H20)3·7H2O (Zn-BTC, BTC = benzene tricarboxylate) and the 2D framework [Zn(BPDC)(H2O)]·H2O (Zn-BPDC, BPDC = 2,2′-bipyridine-5,5′-dicarboxylate) were each grown on Zn-ITO. Physical characterization was carried out using grazing incidence X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Our results show these films were well adhered, homogeneous, self-closing, and of relatively low surface roughness in each case. The ability to vary the dimensionality, metal node, linker, and charge of the EMOF on a conductive transparent substrate opens up a wide range of possible compositions, properties, and applications.

Four new and one previously reported silver 4,4′-vinylenedipyridine (Vpe) coordination polymers were tested as anion exchange materials to assess their potential for pollutant sequestration and compared to analogous silver 4,4′-bipyridine (bipy) coordination polymers. The materials were synthesized using nitrate, tetrafluoroborate, perchlorate, perrhenate, or chromate as the anion to produce cationic coordination polymers with solubilities ranging from 0.0137(7) to 0.21(5) mM. These values are much lower than silver bipy coordination polymers [0.045(3) to 5.5(5) mM] and agree with thermochemical calculations. [Ag(Vpe)+][BF4–], [Ag2(Vpe)2.52+][CrO42–]·5H2O, and [Ag(Vpe)+][ReO4–]·2H2O structures are reported. Perrhenate and chromate ions in an equimolar solution were fully adsorbed by [Ag(Vpe)+][NO3–]·3H2O [620(2) and 137.1(6) mg/g, respectively] as well as by [Ag(Vpe)+][BF4–] [661.8(3) and 190(3) mg/g, respectively] via anion exchange. DFT calculations show that torsional energetics play a significant role in the formation thermodynamics by reducing the energy cost by as much as 4.8 kJ/mol when bipy is replaced with Vpe in silver-based coordination polymers. The results obtained with the flat Vpe ligand highlight the potential role of coordination polymers in practical anion exchange.

The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.

To identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium. Neuropsychological testing was available for 5429–32?070 subjects of European ancestry aged 45 years or older, free of dementia and clinical stroke at the time of cognitive testing from 20 cohorts in the discovery phase. We analyzed performance on the Trail Making Test parts A and B, the Letter Digit Substitution Test (LDST), the Digit Symbol Substitution Task (DSST), semantic and phonemic fluency tests, and the Stroop Color and Word Test. Replication was sought in 1311-21860 subjects from 20 independent cohorts. A significant association was observed in the discovery cohorts for the single-nucleotide polymorphism (SNP) rs17518584 (discovery P-value=3.12 × 10-8) and in the joint discovery and replication meta-analysis (P-value=3.28 × 10-9after adjustment for age, gender and education) in an intron of the gene cell adhesion molecule 2 (CADM2) for performance on the LDST/DSST. Rs17518584 is located about 170?kb upstream of the transcription start site of the major transcript for the CADM2gene, but is within an intron of a variant transcript that includes an alternative first exon. The variant is associated with expression of CADM2in the cingulate cortex (P-value=4 × 10-4). The protein encoded by CADM2is involved in glutamate signaling (P-value=7.22 × 10-15), gamma-aminobutyric acid (GABA) transport (P-value=1.36 × 10-11) and neuron cell-cell adhesion (P-value=1.48 × 10-13). Our findings suggest that genetic variation in the CADM2gene is associated with individual differences in information processing speed.

M4Ag44(p-MBA)30molecular nanoparticles, where M is an alkali metal, have recently been shown to have exceptional stability, which confers unique traits to this molecule. In particular, the synthesis is straightforward, produces a truly single-sized molecular product, and has a quantitative yield. Here we describe in detail the results of experimental and theoretical studies on the synthesis, structure, stability, and electronic and optical properties of M4Ag44(p-MBA)30, including ESI-MS, NMR, optical absorption, IR, TGA, and other measurements as well as DFT and TDDFT calculations. This work deepens our understanding of this important Ag molecule, which should facilitate its use in a wide range of fundamental studies and applications.

Cationic layers: Copper hydroxide ethanedisulfonate consists of cationic sheets (see structure of a [Cu4(OH)6]2+layer; Cu green, O red, H white) with ethanedisulfonate as extraframework counteranion. This material shows excellent anion exchange properties for both organics and metal oxo anion pollutants, with over five times higher adsorption capacity for permanganate than hydrotalcite.

Kationische Schichten: Kupferhydroxidethandisulfonat besteht aus kationischen Schichten (siehe Struktur einer [Cu4(OH)6]2+‐Schicht; grün Cu, rot O, weiß H) mit Ethandisulfonat als Anion für den Ladungsausgleich. Das Material zeigt exzellente Anionenaustauscheigenschaften für sowohl organische als auch Metalloxo‐Schadstoffe. Die Adsorptionskapazität für Permanganat ist dabei fünfmal höher als die von Hydrotalcit.

We have discovered a facile and inexpensive approach to fabricate “nanospider” TiO2thin films with not only an amazing morphology but highly efficient water splitting to produce hydrogen. Our method employs benzene-swollen poly(ethylene glycol) as a sacrificial organic polymer to template the semiconductor thin film. The synthesized TiO2thin films are highly crystalline with optimized particle and channel size to enhance the liquid-semiconductor junction interaction. This enhanced contact area leads to more than twice the water splitting performance than conventional P25 thin films. In addition, the nanospider thin films also outperform P25 films in the photodegradation of toxic organics.

Effects of genetically modified herbicide–tolerant (GMHT) and conventional crop management on invertebrate trophic groups (herbivores, detritivores, pollinators, predators and parasitoids) were compared in beet, maize and spring oilseed rape sites throughout the UK. These trophic groups were influenced by season, crop species and GMHT management. Many groups increased twofold to fivefold in abundance between early and late summer, and differed up to 10–fold between crop species. GMHT management superimposed relatively small (less than twofold), but consistent, shifts in plant and insect abundance, the extent and direction of these effects being dependent on the relative efficacies of comparable conventional herbicide regimes. In general, the biomass of weeds was reduced under GMHT management in beet and spring oilseed rape and increased in maize compared with conventional treatments. This change in resource availability had knock–on effects on higher trophic levels except in spring oilseed rape where herbivore resource was greatest. Herbivores, pollinators and natural enemies changed in abundance in the same directions as their resources, and detritivores increased in abundance under GMHT management across all crops. The result of the later herbicide application in GMHT treatments was a shift in resource from the herbivore food web to the detritivore food web. The Farm Scale Evaluations have demonstrated over 3 years and throughout the UK that herbivores, detritivores and many of their predators and parasitoids in arable systems are sensitive to the changes in weed communities that result from the introduction of new herbicide regimes.

The effects of management of genetically modified herbicide–tolerant (GMHT) crops on adjacent field margins were assessed for 59 maize, 66 beet and 67 spring oilseed rape sites. Fields were split into halves, one being sown with a GMHT crop and the other with the equivalent conventional non–GMHT crop. Margin vegetation was recorded in three components of the field margins. Most differences were in the tilled area, with fewer smaller effects mirroring them in the verge and boundary. In spring oilseed rape fields, the cover, flowering and seeding of plants were 25, 44 and 39 lower, respectively, in the GMHT uncropped tilled margins. Similarly, for beet, flowering and seeding were 34 and 39 lower, respectively, in the GMHT margins. For maize, the effect was reversed, with plant cover and flowering 28 and 67 greater, respectively, in the GMHT half. Effects on butterflies mirrored these vegetation effects, with 24 fewer butterflies in margins of GMHT spring oilseed rape. The likely cause is the lower nectar supply in GMHT tilled margins and crop edges. Few large treatment differences were found for bees, gastropods or other invertebrates. Scorching of vegetation by herbicide–spray drift was on average 1.6 on verges beside conventional crops and 3.7 beside GMHT crops, the difference being significant for all three crops.

The effects of the management of genetically modified herbicide–tolerant (GMHT) crops on the abundances of aerial and epigeal arthropods were assessed in 66 beet, 68 maize and 67 spring oilseed rape sites as part of the Farm Scale Evaluations of GMHT crops. Most higher taxa were insensitive to differences between GMHT and conventional weed management, but significant effects were found on the abundance of at least one group within each taxon studied. Numbers of butterflies in beet and spring oilseed rape and of Heteroptera and bees in beet were smaller under the relevant GMHT crop management, whereas the abundance of Collembola was consistently greater in all GMHT crops. Generally, these effects were specific to each crop type, reflected the phenology and ecology of the arthropod taxa, were indirect and related to herbicide management. These results apply generally to agriculture across Britain, and could be used in mathematical models to predict the possible long–term effects of the widespread adoption of GMHT technology. The results for bees and butterflies relate to foraging preferences and might or might not translate into effects on population densities, depending on whether adoption leads to forage reductions over large areas. These species, and the detritivore Collembola, may be useful indicator species for future studies of GMHT management.

The effects of herbicide management of genetically modified herbicide–tolerant (GMHT) beet, maize and spring oilseed rape on the abundance and diversity of soil–surface–active invertebrates were assessed. Most effects did not differ between years, environmental zones or initial seedbanks or between sugar and fodder beet. This suggests that the results may be treated as generally applicable to agricultural situations throughout the UK for these crops. The direction of the effects was evenly balanced between increases and decreases in counts in the GMHT compared with the conventional treatment. Most effects involving a greater capture in the GMHT treatments occurred in maize, whereas most effects involving a smaller capture were in beet and spring oilseed rape. Differences between GMHT and conventional crop herbicide management had a significant effect on the capture of most surface–active invertebrate species and higher taxa tested in at least one crop, and these differences reflected the phenology and ecology of the invertebrates. Counts of carabids that feed on weed seeds were smaller in GMHT beet and spring oilseed rape but larger in GMHT maize. In contrast, collembolan detritivore counts were significantly larger under GMHT crop management.

We compared the effects of the management of genetically modified herbicide–tolerant (GMHT) and conventional beet, maize and spring oilseed rape on 12 weed species. We sampled the seedbank before and after cropping. During the season we counted plants and measured seed rain and biomass. Ratios of densities were used to calculate emergence, survival, reproduction and seedbank change. Treatments significantly affected the biomass of six species in beet, eight in maize and five in spring oilseed rape. The effects were generally consistent, with biomass lower in GMHT beet and spring oilseed rape and higher in GMHT maize. With few exceptions, emergence was higher in GMHT crops. Subsequent survival was significantly lowered for eight species in beet and six in spring oilseed rape in the GMHT treatments. It was increased for five species in maize and one in spring oilseed rape. Significant effects on seedbank change were found for four species. However, for many species in beet and spring oilseed rape (19 out of 24 cases), seed densities were lower in the seedbank after GMHT cropping. These differences compounded over time would result in large decreases in population densities of arable weeds. In maize, populations may increase.

We compared the seedbanks, seed rains, plant densities and biomasses of weeds under two contrasting systems of management in beet, maize and spring oilseed rape. Weed seedbank and plant density were measured at the same locations in two subsequent seasons. About 60 fields were sown with each crop. Each field was split, one half being sown with a conventional variety managed according to the farmer's normal practice, the other half being sown with a genetically modified herbicide–tolerant (GMHT) variety, with weeds controlled by a broad–spectrum herbicide. In beet and rape, plant densities shortly after sowing were higher in the GMHT treatment. Following weed control in conventional beet, plant densities were approximately one–fifth of those in GMHT beet. In both beet and rape, this effect was reversed after the first application of broad–spectrum herbicide, so that late–season plant densities were lower in the GMHT treatments. Biomass and seed rain in GMHT crops were between one–third and one–sixth of those in conventional treatments. The effects of differing weed–seed returns in these two crops persisted in the seedbank: densities following the GMHT treatment were about 20 lower than those following the conventional treatment. The effect of growing maize was quite different. Weed density was higher throughout the season in the GMHT treatment. Late–season biomass was 82 higher and seed rain was 87 higher than in the conventional treatment. The difference was not subsequently detectable in the seedbank because the total seed return was low after both treatments. In all three crops, weed diversity was little affected by the treatment, except for transient effects immediately following herbicide application.