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The effect of water on CO oxidation over a Au/Fe2O3 catalyst, fabricated by dispersing 2.3 nm Au particles on a rod-shaped Fe2O3, was examined comprehensively. Under the dry gas condition (a CO/O2 ...

Water has been proven to be an effective additive to enhance the growth rate and purity of the synthesized carbon nanotubes (CNTs) in the chemical vapor deposition (CVD) method. Due to similar CNT ...

Machine learning (ML) is recognized as an efficient prediction tool. However, very few attempts have been made to apply it to model pressure losses in the water-assisted pipeline transportation of ...

Taking advantage of the dynamic covalent chemistry approach, four different cages were synthesized by condensation of tripodal pseudopeptides with 4,4′-biphenyldicarboxyaldehyde. Whereas undesired products of polymeric nature were obtained in polar solvents, the [3+2] cryptand-type macrobicyclic architectures were obtained in excellent yields using chloroform as solvent, even at relatively high concentrations. The presence of two encapsulated water molecules may provide a positive template effect in the low polarity medium. The final macrobicycles display a combination of two types of chirality: d,l chirality due to the asymmetric α-C centers and P,M helical chirality. The homochiral helicity found for all the enantiomerically pure molecular cages indicates strong chirality induction by the asymmetric α-C. Besides, the self-sorting properties of the different chiral pseudopeptides have been studied, resulting in high-fidelity homo-self-sorting. DFT calculations point out that the self-sorting outcome may also be a direct result of the encapsulation of two water molecules within the cavity.

Efficient and green exfoliation of bulk MoS2 into few-layered nanosheets in the semiconducting hexagonal phase (2H-phase) remains a great challenge. Here, we developed a new method, water-assisted exfoliation (WAE), for the scalable synthesis of carboxylated chitosan (CC)/2H-MoS2 nanocomposites. With facile hand grinding of the CC powder, bulk MoS2 and water followed by conventional liquid-phase exfoliation in water, this method can not only efficiently exfoliate the 2H-MoS2 nanosheets, but also produce two-dimensional (2D) CC/2H-MoS2 nanocomposites. Interestingly, the intercalated CC in MoS2 nanosheets increases the interlayer spacing of 2H-MoS2 to serve as good candidates for the semiconductor devices. 2D CC/2H-MoS2 nanocomposites show superior electronic rectification effects in nonvolatile write-once-read-many-times memory (WORM) behavior with an ON/OFF ratio over 103, which can be rationally controlled by the weight ratios of CC and MoS2. These findings by the WAE method would open tremendous potential opportunities to prepare commercially available semiconducting 2D nanocomposites for promising high-performance device applications.

Solvent-dependent magnetism in Cu-based metal-organic frameworks (MOFs) is reported. Spin-flop magnetic behaviour occurs at different dehydrated states of MOFs. The oxygens of guest and coordinated water molecules are responsible as water removal tunes the coordination geometry around the Cu centre and the electronic structure of the framework.

In the present work, a one-dimensional metal-organic framework, {[Zn3(TBIB)2(Cl)6]11H2O}n (1), has been synthesized under high temperature and acidic conditions by utilizing the tripodal ligand 1,...

In this work, we report on a facile one-pot synthesis route to obtain Pd nanocubes (PdNCs) in water assisted by halide ions and poly(vinylpyrrolidone) under the precise control of acid etching. Whi...

A miniaturized inline Fabry-Perot interferometer fabricated by fs laser direct writing in the water has been proposed. The performances of the Fabry-Perot interferometers fabricated in the deionize...

Water-assisted proton transport through confined spaces influences many phenomena in biomolecular and nanomaterial systems. In such cases, the water molecules that fluctuate in the confined pathways provide the environment and the medium for the hydrated excess proton migration via Grotthuss shuttling. However, a definitive collective variable (CV) that accurately couples the hydration and the connectivity of the proton wire with the proton translocation has remained elusive. To address this important challenge—and thus to define a quantitative paradigm for facile proton transport in confined spaces—a CV is derived in this work from graph theory, which is verified to accurately describe water wire formation and breakage coupled to the proton translocation in carbon nanotubes and the Cl(−)/H(+) antiporter protein, ClC-ec1. Significant alterations in the conformations and thermodynamics of water wires are uncovered after introducing an excess proton into them. Large barriers in the proton translocation free-energy profiles are found when water wires are defined to be disconnected according to the new CV, even though the pertinent confined space is still reasonably well hydrated and—by the simple measure of the mere existence of a water structure—the proton transport would have been predicted to be facile via that oversimplified measure. In this paradigm, however, the simple presence of water is not sufficient for inferring proton translocation, since an excess proton itself is able to drive hydration, and additionally, the water molecules themselves must be adequately connected to facilitate any successful proton transport.

Incorporation of water has been revealed to successfully facilitate visible-light photoredox catalysis of indole leading to increased production of C2-quaternary indolinone. The water-promoted photoreaction of indole under catalyst-free conditions by a household compact fluorescence light was also demonstrated. The antiproliferative activity of the synthesized indolinones was evaluated against three human cancer cell lines.

We report that water can repeatedly be decomposed and regenerated in molten LiCl at 680 °C under a low cell voltage of only 1 V, and these interactions lead to the clean production and in situ consumption of hydrogen, and, consequently, to the electro-reduction of cobalt oxide to highly faceted cobalt microcrystals with a dominant stable face-centered cubic (fcc) phase with an energy consumption of 1150 kW h per ton of reduced cobalt, providing considerable advantages over the alternative approaches available for cobalt production. The phase and morphological evolution that occurred is shown to follow the sequence: CoO → Co3O4 → Li0.065Co0.935O → Co. The establishment of the desirable high temperature fcc–Co phase at room temperature, observed in this study, is related to the doping of Co crystals with hydrogen. The mechanism involved in the water-assisted clean electro-reduction of cobalt oxide is systematically investigated.

For the first time, a simple yet efficient water-assisted one-pot pyrolysis (WAOP) strategy was developed to in situ liberate the inaccessible Ru active sites confined inside N-doped carbon. The liberated Ru/CN catalysts exhibit a 9-fold improvement in catalytic activity for quinoline hydrogenation compared with catalysts obtained from the water-free pyrolysis process, and high tolerance for selective hydrogenation of various quinolines substituted with different functional groups. We anticipate that WAOP addresses a key issue that currently plagues carbon-based catalyst synthesis and should lead to improvements in fields as diverse as chemical production and environmental protection.

We report a novel strategy to identify reduced and oxidized glutathiones by employing an STM break junction technique. A mechanism involving a water-assisted hydrogen bond is proposed for the charge transport through the oxidized glutathione junction, and this is verified by both experimental and theoretical findings.

Bimetallic platinum–cobalt (Pt–Co) catalysts have highly enhanced performance for the oxygen reduction reaction (ORR), where this peculiar surface alloy structure contributes to efficient energy co...

The photoreaction of 2,3,4',5-tetrahydroxystilbene-2-O-β-d-glucoside (TSG) has been investigated. Water-assisted/water-accelerated photodimerization of trans-TSG favored the formation of syn-head-to-tail [2 + 2] photocyclobutane under 365 nm irradiation as a result of hydrophobic association and a fluorescent solute-solute aggregate from their excited singlet states. In contrast, irradiation with 254 nm led to [2 + 2] photocycloreversion. The two cyclobutane dimers were first obtained through straightforward photoreaction and identified as multiflorumiside A and multiflorumiside C through the detailed analysis of high-resolution electrospray ionization mass spectrometry and one- and two-dimensional nuclear magnetic resonance. Therefore, trans-TSG should be protected from light and water.

Semiconductor photocatalysis is a sustainable and advanced method for depollution and energy shortage, yet efficient photocatalysts have to be synthesized. For instance, BiOCl is a promising photocatalyst, but its efficiency is largely dependent on morphology. In particular, there is a need for simple synthesis procedures and easily controllable facet exposure. Here, nanosheet-assembled BiOCl nanoflowers with exposed {001} facets were prepared by a rapid, efficient, water-assisted synthesis. BiOCl nanoflowers exhibited 3.3 times better adsorption and 3.5 times superior photosensitized degradation of rhodamine B under visible light irradiation, compared with BiOCl nanosheets. These improvements are attributed to the higher exposition of the {001} facet and 3D hierarchical structure. This work offers new insights to better understand the photosensitized degradation and rational design of highly active photocatalysts.

A water-assisted control of Pt nanoparticle size during a surfactant-free, microwave-assisted polyol synthesis of the carbon-supported platinum nanoparticles (Pt/C) in a mixture of ethylene glycol and water using (NH4)2PtCl6 as the Pt precursor is demonstrated. The particle size was tuned between ∼2 and ∼6 nm by varying either the H2O volume percent or the Pt precursor concentration during synthesis. The electrochemical surface area (ECSA) and the oxygen-reduction reaction activity obtained for the Pt/C electrocatalyst show a catalytic performance competitive to that of the state-of-the-art commercial Pt/C electrocatalysts used for polymer electrolyte membrane fuel cell electrodes (ECSA: ∼70 m2/g; half-wave potential for oxygen reduction reaction: 0.83 V vs reversible hydrogen electrode). The synthesized Pt/C electrocatalysts show durability equivalent to or better than that of the commercial Pt/C. The durability was found to improve with increasing particle size, with the ECSA loss values being ∼70 and ∼55% for the particle sizes of 2.1 and 4.3 nm, respectively. The study may be used as a route to synthesize Pt/C electrocatalysts from a convenient and economic Pt precursor (NH4)2PtCl6 and avoiding the use of alkaline media.

The high specific activity and cost-effectiveness of single-atom catalysts (SACs) hold great promise for numerous catalytic chemistries. In hydrogenation reactions, the mechanisms of critical steps...

N-doped well-aligned thin multiwall carbon nanotubes (CNTs) have been prepared by a facile water-assisted chemical vapor deposition (CVD) process using melamine as both the carbon precursor...

Fresh produce are vulnerable to pathogens during pre- and postharvest stages. Most fresh vegetable and fruits are consumed directly or merely washed with chlorine. We investigated two emerging decontamination technologies, pulse light (PL) and ultraviolet (UV), in combination with washing (referred as water-assisted PL [WPL] and water-assisted UV [WUV]). Blueberries, grape tomatoes, and iceberg lettuce shreds were tested in this study to represent fresh vegetables and fruits with smooth and rough surfaces. Salmonella spp. were used as a model microorganism due to its prevalence in outbreaks. Spot-inoculation and dip-inoculation were used to simulate potential contaminations during irrigation, harvest, transportation, and processing. Two intensity levels of PL (∼0.15 and 0.3 J/cm2 per pulse; 3 pulses/s) and UV (∼13 and 28 mW/cm2 ) were tested for 1 and 2 min. For all three types of fresh produce, blueberries, grape tomatoes, and iceberg lettuce shreds, WPL and WUV showed similar Salmonella inactivation effects on fresh produce. For spot-inoculated fresh produce, WPL and WUV treatments reduced 4.5 to 5.7, 4.4 to 5.4, and 1.9 to 3.1 logs of Salmonella on blueberries, tomatoes, and lettuce shreds, respectively. For dip-inoculated fresh produce, WPL and WUV treatments reduced 1.8 to 2.3, 1.9 to 2.5, and 1.9 to 2.6 logs of Salmonella on blueberries, tomatoes, and lettuce shreds, respectively. The majority of the WUV and WPL treatments could eliminate Salmonella in the wash water for blueberries and tomatoes, but not for lettuce. PRACTICAL APPLICATION: Two light systems, pulsed light and UV, for decontamination of fresh produce were evaluated and compared. Results demonstrated that the two systems showed similar decontamination effect on fresh produce, demonstrating that the UV system could be used to replace the pulsed light system to reduce equipment cost.; © 2019 Institute of Food Technologists®.

We previously demonstrated that remote infrared Matrix Assisted Laser Desorption Ionization technology (Spidermass) using endogenous water as matrix (or so called water assisted laser desorption/ionization) was enabling real-time in vitro and in vivo analysis of clinical pathological tissues. In the present work, Spidermass was used to biotype human pathogens either from liquid bacteria growth in time course, from petri dish or on smears. Reproducibility experiments as well as bacteria dispersion and lipids identifications with SpiderMass in MS/MS mode were undertaken. The whole of the data establish that SpiderMass instrument allows real time bacteria biotyping and can be useful in clinic for pathogen identification.

A thermally-induced intramolecular [4+2] cycloaddition reaction of allylamino- or allyloxy-tethered alkylidenecyclopropanes has been reported in this paper, giving a new protocol for the rapid construction of polycyclic skeleton molecules in moderate to excellent yields with a broad substrate scope. On the basis of control experiments and DFT calculations, we disclosed that the reaction proceeded through a [4+2] cycloaddition and trace of water assisted 1,3-H shift processes to give the target product.

As a 100% atom-economy process, direct oxidation of methane into methanol remains as a grand challenge due to the dilemma between activation of methane and over-oxidation of methanol. Here, we report that water enabled mild oxidation of methane into methanol with >99% selectivity over Au single atoms on black phosphorus (Au1/BP) nanosheets under light irradiation. The mass activity of Au1/BP nanosheets reached 113.5 μmol gcatal−1 in water pressured with 33 bar of mixed gas (CH4:O2 = 10:1) at 90 °C under light irradiation (1.2 W), while the activation energy was 43.4 kJ mol−1. Mechanistic studies revealed that water assisted the activation of O2 to generate reactive hydroxyl groups and •OH radicals under light irradiation. Hydroxyl groups reacted with methane at Au single atoms to form water and CH3* species, followed by oxidation of CH3* via •OH radicals into methanol. Considering the recycling of water during the whole process, we can also regard water as a catalyst., It is important but challenging to oxidize methane by O2 into methanol under ambient conditions. Here, the authors achieved mild oxidation of methane into methanol over Au single atoms on black phosphorus nanosheets with the help of water under light irradiation.

Chemistry of materials 33(18), 7337 - 7349 (2021). doi:10.1021/acs.chemmater.1c01755, While two-dimensional (2D) materials may preserve some intrinsic properties of the corresponding layered bulk material, new characteristics arise from their pronounced anisotropy or confinement effects. Recently, exceptionally high ionic conductivities were discovered in 2D materials such as graphene oxide and vermiculite. Here, we report on the water-assisted fast conduction of lithium ions in restacked lithium tin sulfide nanosheets. Li$_{0.8}$Sn$_{0.8}$S$_2$ exfoliates spontaneously in water and can be restacked into homogeneous films in which the lithium content is decreased, and a partial substitution of sulfur with hydroxyl groups takes place. Using a recursive supercell refinement approach in reciprocal space along with real-space pair distribution function analysis, we describe restacked lithium tin sulfide as a partially turbostratically disordered material composed of lithium-containing and lithium-depleted layers. In humid air, the material takes up multiple layers of water that coordinate lithium ions in the space between the layers, increasing the stacking distance and screening the interaction between lithium ions and the anionic layers. This results in a 1000-fold increase in ionic conductivity up to 47 mS cm$^{���1}$ at high humidities. Orientation-dependent impedance spectroscopy suggests a facile in-plane conduction and a hindered out-of-plane conduction. Pulsed field gradient nuclear magnetic resonance spectroscopy reveals a fast, simultaneous diffusion of a majority and a minority species for both 7Li and 1H, suggesting water-assisted lithium diffusion to be at play. This study enlarges the family of nanosheet-based ionic conductors and helps to rationalize the transport mechanism of lithium ions enabled by hydration in a nanoconfined 2D space., Published by American Chemical Society, Washington, DC

We aimed to study the efficacy of a water-assisted UVC light device (WUVC) as an innovative clean technology for the disinfection of fresh sound tomatoes and processing wash water and water turbidity was evaluated as a critical parameter. First, wash waters with different turbidities (from 0.4 to 828 NTU) were inoculated with Listeria innocua and treated in the WUVC device at different dosages. Secondly, fresh tomatoes, inoculated with L. innocua and non-inoculated ones, were treated using the WUVC device containing wash water of different turbidities for different times. The reduction of L. innocua populations on wash water and on the surface of tomato was influenced by turbidity; lower reduction values were observed at higher turbidities. Washing tomatoes with tap water with UVC lamps off (control treatment, TW) decreased L. innocua population on the surface of tomatoes but did not eliminate those bacteria that went into the water. Contrarily, when UVC lights were on, L. innocua population in wash water after treatment significantly decreased, those in clean water being the lowest populations. Reductions of native microbiota on the clean water treated with the highest UV-C radiation dose were lower than those obtained when tomatoes were artificially inoculated. We demonstrated that high reductions of L. innocua population on fresh tomatoes could be achieved using the WUVC system but some drawbacks related to the increase of turbidity should be solved for its implementation in real conditions. The authors are grateful to TECALZIM Research Project (Mitigation Strategies to Reduce the Microbial Risks and Improve the Quality and Safety of Frozen and Ready-to-Eat Strawberries) which was funded by the Spanish Ministry of Economy, Industry, and Competitiveness (RTC- 2016-5498-2) and CERCA Programme (Generalitat de Catalunya) for its financial support. I. Aguil´o-Aguayo thanks the Spanish Ministry of Economy, Industry and Competitiveness and the European Social Fund for the Postdoctoral Senior Grant Ramon y Cajal (RYC-2016-19949). Thanks are also given to Marina Anguera for her technical assistance.

Aflatoxin B1 (AFB1) is one of the most commonly found mycotoxin in corn, which is highly toxic, carcinogenic, teratogenic, and mutagenic for the health of humans and animals. In order to reduce the AFB1 in corn, corn kernels were processed with Water-assisted Microwaves Treatment (WMT) and the feasibility of WMT processing on AFB1 reduction and its effects on corn quality were analyzed. Increasing the treatment time and microwave power could increase the reduction of AFB1, and the maximum reduction rate could reach 58.6% and 56.8%, respectively. There was no significant correlation between the initial concentration of AFB1 and the reduction rate of AFB1. During WMT, the main toxigenic molds were sterilized completely, and the moisture content of corn climbed up and then declined to the initial level. WMT could obviously increase the fatty acid value and pasting temperature of corn and reduce the all paste viscosity of corn. However, it had little effect on the color of corn. The results indicated that WMT could reduce AFB1 effectively and avoid the vast appearance of heat-damaged kernels simultaneously. Undoubtedly, water played an important role in WMT. This result provides a new idea for the reduction of AFB1 by microwave.

The first desymmetrization of gem-diols forming chiral hemiketal carbons was accomplished via organocatalytic enantio- and diastereoselective cycloetherification, which afforded optically active tetrahydropyrans containing a chiral hemiketal carbon and tetrasubstituted stereocenters bearing synthetically versatile fluorinated groups. The desymmetrization of silanediols was also demonstrated as an asymmetric route to chiral silicon centers.

Background and Aims Since 2008, a plethora of research studies has compared the efficacy of water-assisted (aided) colonoscopy (WAC) and underwater resection (UWR) of colorectal lesions with standard colonoscopy. We reviewed and graded the research evidence with potential clinical application. We conducted a modified Delphi consensus among experienced colonoscopists on definitions and practice of water immersion (WI), water exchange (WE), and UWR. Methods Major databases were searched to obtain research reports that could potentially shape clinical practice related to WAC and UWR. Pertinent references were graded (Grading of Recommendations, Assessment, Development and Evaluation). Extracted data supporting evidence-based statements were tabulated and provided to respondents. We received responses from 55 (85% surveyed) experienced colonoscopists (37 experts and 18 nonexperts in WAC) from 16 countries in 3 rounds. Voting was conducted anonymously in the second and third round, with ≥80% agreement defined as consensus. We aimed to obtain consensus in all statements. Results In the first and the second modified Delphi rounds, 20 proposed statements were decreased to 14 and then 11 statements. After the third round, the combined responses from all respondents depicted the consensus in 11 statements (S): definitions of WI (S1) and WE (S2), procedural features (S3-S5), impact on bowel cleanliness (S6), adenoma detection (S7), pain score (S8), and UWR (S9-S11). Conclusions The most important consensus statements are that WI and WE are not the same in implementation and outcomes. Because studies that could potentially shape clinical practice of WAC and UWR were chosen for review, this modified Delphi consensus supports recommendations for the use of WAC in clinical practice.

ObjectivesThe English Bowel Cancer Screening Programme invites 55 year olds for a sigmoidoscopy (Bowel Scope Screening (BSS)), aiming to resect premalignant polyps, thus reducing cancer incidence. A national patient survey indicated higher procedural pain than anticipated, potentially impacting on screening compliance and effectiveness. We aimed to assess whether water-assisted sigmoidoscopy (WAS), as opposed to standard CO2 technique, improved procedural pain and detection of adenomatous polyps.DesignThe WASh (Water-Assisted Sigmoidoscopy) trial was a multicentre, single-blind, randomised control trial for people undergoing BSS. Participants were randomised to either receive WAS or CO2 from five sites across England. The primary outcome measure was patient-reported moderate/severe pain, as assessed by patients on a standard Likert scale post procedure prior to discharge. The key secondary outcome was adenoma detection rate (ADR). The costs of each technique were also measured.Results1123 participants (50% women, mean age 55) were randomised (561 WAS, 562 CO2). We found no difference in patient-reported moderate/severe pain between WAS and CO2 (14% in WAS, 15% in CO2; p=0.47). ADR was 15% in the CO2 arm and 11% in the WAS arm (p=0.03); however, it remained above the minimum national performance standard in both arms. There was no statistical difference in mean number of adenomas nor overall polyp detection rate. There was negligible cost difference between the two techniques.ConclusionIn the context of enema-prepared unsedated screening sigmoidoscopies performed by screening-accredited endoscopists, no difference in patient-reported pain was seen when using either a CO2 or WAS intubation technique.Trial registration numberISRCTN81466870.

The manuscript revolves around an interesting observation of solidification of a solution of N-((1-((1-ethyl-1H-benzo[d]imidazol-2-yl)methyl)-1H-1,2,3-triazole-4-yl)methyl)aniline (A6) in the NMR tube after around 12 h. Real-time images showed fibrillar and spherulitic growth with tip branching and side branching, which is thermoreversible. The compound under investigation is unique because it is synthesized to understand the anticancer activity with two pharmacophores, benzimidazole and triazole. Click chemistry is employed for in situ generation of triazole moiety on benzimidazole. Previously, benzimidazole-based compounds have shown self-aggregation-induced gel-like behavior because of hydrogen bonding and/or π–π stacking interactions. In the present case, NMR titrations with D2O addition showed two distinct changes in the chemical shift for methylene bridges (connecting benzimidazole and triazole ring) and ortho protons of the phenyl ring (attached to triazole ring). Interestingly, a single-crystal X-ray structure shows the absence of hydrogen bonds and π–π stacking while in the presence of only two distinct close contacts, completely correlating NMR data discussed in detail. A similar “molecular origin” for self-aggregation is observed in seven other flexible but regioisomeric compounds, which were designed and synthesized for inducing hydrogen bonding through the removal of N-ethyl group and insertion of aniline and/or fluoro group.

With water as an eco-friendly heterogeneous nucleation accelerator, silver nanowires (Ag NWs) have been successfully prepared with a high aspect ratio (>1600). The Ag NW-based film exhibits a low sheet resistance of 8.1 Ω sq−1 with a transparency of 81.9% at 550 nm, showing the potential application of electrode materials in polymer solar cells.

There have been great developments in shape memory polymers in recent years. However, the permanent shape was usually predetermined and could not be changed during the shape memory process. This work reports a facile method for permanent shape reconfiguration of shape memory polymers using a water-soaking treatment. The impact of water molecules on the structure, morphology, and properties of zwitterionic polyurethanes (ZPUs) was carefully investigated. FT-IR, DSC, TGA, and DMA analysis revealed that polymer chains of ZPU can be easily activated by absorbing water molecules and was solidified again by removal of water molecules. Direct water-soaking treatment can eliminate previous shape recovery capability and then be used to reconfigure a new permanent shape for a new thermally induced shape memory process. Thus, this work provides an alternative approach for manufacturing complicated devices at room temperature and for easily regulating the thermally induced shape memory effect.