Lower Reaction Time Research Articles

Higher judgements of learning for emotional words: processing fluency or memory beliefs?

ABSTRACT Previous research has shown that emotionally-valenced words are given higher judgements of learning (JOLs) than are neutral words. The current study examined potential explanations for this emotional salience effect on JOLs. Experiment 1 replicated the basic emotionality/JOL effect. In Experiments 2A and 2B, we used pre-study JOLs and assessed memory beliefs qualitatively, finding that, on average, participants believed that positive and negative words were more memorable than neutral words. Experiment 3 utilised a lexical decision task, resulting in lower reaction times (RTs) for positive words than for neutral words, but equivalent RTs for negative and neutral words, suggesting that processing fluency may partially account for higher JOLs for positive words, but not for negative words. Finally, we conducted a series of moderation analyses in Experiment 4 which assessed the relative contributions of fluency and beliefs to JOLs by measuring both factors in the same participants, showing that RTs made no significant contribution to JOLs for either positive or negative words. Our findings suggest that although positive words may be more fluently processed than neutral words, memory beliefs are the primary factor underlying higher JOLs for both positive and negative words.

Validation of a Novel Reaction Time Test Specific for Military Personnel

A military-specific reaction time (RT) test was developed to explore its reliability and sensitivity to discriminate between military personnel and sport science students. Fifteen male professional Spanish soldiers and 16 male sport science students completed two RT test modalities: military-specific and nonspecific RT tests. For each RT test modality, both the Simple (i.e.,one stimulus, one response) and the Go, No-Go RT (i.e.,true, and false stimuli, one response) were tested. The military-specific RT test consisted of a video presented through virtual reality glasses of a forest environment in which soldiers would appear from behind different bushes (stimuli) and the response consisted of pressing the button of a gun-shaped mouse (when they saw a soldier pointing a rifle at them). Both Simple and Go, No-Go RT reached acceptable reliability in both populations (coefficient of variation ≤ 9.64%). Military personnel presented a lower RT than sport science students during the military-specific RT test (p ≤ .001), while no differences were obtained during the nonspecific RT test. RT values were not significantly correlated between the military-specific and nonspecific RT tests (r ≤ .02). These findings collectively suggest that the novel military-specific RT test is an ecologically valid alternative to evaluate the information processing abilities of military personnel.

A new approach to the epoxidation of natural rubber through a sonochemical method

In this study, epoxidized natural rubber (ENR) was synthesized using a sonochemical method. Acoustic cavitation was employed for the epoxidation reaction instead of heat and agitation. The effects of reaction time and temperature on the epoxidation degree (EPD) were studied. The chemical structure and EPD of ENR were assessed by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) techniques. At low reaction times (≤45 min), the EPD was independent of the reaction temperature but tended to increase with increasing reaction time. However, at sufficiently long reaction times (>45 min), the EPD depended on both reaction time and temperature, i.e., it increased slightly with an increase in reaction time up to 60 min before leveling off at the reaction temperatures of 20 °C and 30 °C. However, at a higher reaction temperature (40 °C), it tended to decline slowly with increasing reaction time, possibly due to the ring-opening reaction. The highest EPD, at approximately 30%, was achieved when synthesized by a sonochemical method at 30 °C for 60 min, which is equivalent to that of the ENR synthesized by a conventional method at 60 °C for 6 h. The properties of the raw ENR samples (with ∼30% epoxidation) prepared by different methods were also investigated. It was found that the ENR sample prepared by the sonochemical method possessed a slightly higher viscosity, initial plasticity number, and plasticity retention index than the ENR sample prepared by the conventional method. The results reveal the potential of the sonochemical method to supplant the conventional method for ENR synthesis, as it requires a considerably lower reaction temperature and time.

Residential green space improves cognitive performances in primary schoolchildren independent of traffic-related air pollution exposure

BackgroundCognitive performances of schoolchildren have been adversely associated with both recent and chronic exposure to ambient air pollution at the residence. In addition, growing evidence indicates that exposure to green space is associated with a wide range of health benefits. Therefore, we aimed to investigate if surrounding green space at the residence improves cognitive performance of primary schoolchildren while taking into account air pollution exposure.MethodsCognitive performance tests were administered repeatedly to a total of 307 primary schoolchildren aged 9-12y, living in Flanders, Belgium (2012–2014). These tests covered three cognitive domains: attention (Stroop and Continuous Performance Tests), short-term memory (Digit Span Forward and Backward Tests), and visual information processing speed (Digit-Symbol and Pattern Comparison Tests). Green space exposure was estimated within several radii around their current residence (50 m to 2000 m), using a aerial photo-derived high-resolution (1 m2) land cover map. Furthermore, air pollution exposure to PM2.5 and NO2 during the year before examination was modelled for the child’s residence using a spatial–temporal interpolation method.ResultsAn improvement of the children’s attention was found with more residential green space exposure independent of traffic-related air pollution. For an interquartile range increment (21%) of green space within 100 m of the residence, a significantly lower mean reaction time was observed independent of NO2 for both the sustained-selective (-9.74 ms, 95% CI: -16.6 to -2.9 ms, p = 0.006) and the selective attention outcomes (-65.90 ms, 95% CI: -117.0 to -14.8 ms, p = 0.01). Moreover, green space exposure within a large radius (2000 m) around the residence was significantly associated with a better performance in short-term memory (Digit-Span Forward Test) and a higher visual information processing speed (Pattern Comparison Test), taking into account traffic-related exposure. However, all associations were attenuated after taking into account long-term residential PM2.5 exposure.ConclusionsOur panel study showed that exposure to residential surrounding green space was associated with better cognitive performances at 9–12 years of age, taking into account traffic-related air pollution exposure. These findings support the necessity to build attractive green spaces in the residential environment to promote healthy cognitive development in children.

The assessment of effectiveness of a novel antidepressant, Agomelatine on anxiety and depression induced by fluoride intoxication by means of Open-Field and Hot-Plate tests in mouse model (BalB-C)

It is well known that fluoride (F) poisoning causes anxiety and depression, and Agomelatine, an analogue of melatonin, has been reported to be effective on anxiety and depression. Therefore, the aim of this study is to investigate the short-term efficacy of Agomelatine application on anxiety and depression caused by F intoxication via Open-Field and Hot-Plate tests. Forty male BalB-C mice, aged 5-6 months, constituted the research material for this study. Subjects were randomly divided into 4 groups (Healthy-Control, Fluorosis-Control, 25 mg/kg Agomelatine, 50 mg/kg Agomelatine). Healthy-Control group (HC) received tap water, containing 0.3 ± 0.05 mgF/L. Fluorosis-Control group (F) received drinking water containing 40 mgF/L. Other two experimental groups (25 and 50) received drinking water containing 40 mgF/L and a single dose of Agomelatine (25 and 50 mg/kg respectively). The effect of Agomelatine on anxiety and depression induced by high dose F was evaluated using Open-Field and Hot-Plate tests compared to control groups. Fluorosis caused to decrease in Rearing, Grooming and Square numbers of Open-Field test and to increase Defecation counts (P<0.05). Agolematine applications enabled to normalize the Open-Field Test data. Similarly, according to the Hot-Plate findings, low reaction time caused by fluorosis increased in Agomelatine groups (P<0.05). According to those results, psychological improvement was observed in patients with fluorosis compared to the control group after Agomelatine applications. Consequently, according to Open-Field and Hot-Plate tests findings, it could be concluded that Agomelatine has a curative effect on anxiety and depression induced by F toxicity.

Fundamentals and Manipulation of Bare Droplets and Liquid Marbles as Open Microfluidic Platforms

Microfluidics, as one of the most valuable analytical technologies of this century, has played an important role in various fields. Particularly, out-of-channel microfluidics, often referred to as open microfluidics (OMF) has recently drawn wide research attention among scholars for its great potential in convenient manual intervention. Much recent research has been geared toward bare droplets and particle-armed droplets (namely liquid marbles, LMs), which could serve as independent systems in OMF. Their versatile applications include but are not limited to nanomaterials preparation, energy harvesting, cell culture and environment monitoring. These applications are mainly attributed to the excellent independence, low reagent consumption and short reaction time of separate droplets and LMs. In addition, more operation features, such as diverse handling options, flexible controllability and high precision, further enable droplets and LMs carrying small liquid biochemical samples to be manipulated in an open environment freely. Considering the emergence of important research on bare droplets and LMs, this paper systematically reviews the state of the art in the fundamentals and manipulation of the two novel platforms under the frame of OMF. First, the intrinsic property of bare droplets on solid substrates, especially on superhydrophobic ones, is discussed, followed by the formation mechanism of nonwetting LMs and the effect of coating particles on LMs’ performance. Then, friction obstacles and actuation principles raised in driving droplets and LMs are further analyzed theoretically. Subsequently, several classical types of manipulation tasks for both droplets and LMs, namely transportation, coalescence, mixing and splitting, are discussed with a focus on key techniques to accomplish the tasks aforementioned. Finally, the fundamental and manipulation similarities and differences between bare droplets and LMs are summarized and future developments towards droplet- or LM-based microreactors and microsensors are recommended accordingly.

Synthesis of Catalyst Using Bio‐benign Precursors and Its Application in One‐Pot Catalytic Synthesis of Imidazo[1,2‐a]pyridines

AbstractDevelopment of catalysts using natural feedstock is the need of the current era, and accordingly, we have developed a new ligand N‐(2‐hydroxynapthylidene)‐L‐leucienyl‐4,6‐O‐ethylidene‐β‐D‐glucopyranosylamine using natural occurring D‐glucose and L‐amino acid. It interacts with several bio‐relevant metal ions like iron, copper, zinc, etc., but its association with cupric ions is immune to pH (4.2–9.1) change. In‐situ copper‐catalyzed reactions have been proven to be pivotal in many important organic syntheses, including imidazo[1,2‐a]pyridines, which is one of the important precursors of many drug molecules. Catalytic synthesis of imidazo[1,2‐a]pyridines requires high catalyst loading, hazardous solvent, high temperature, and long reaction time, which are major drawbacks towards green synthetic methodology. Interestingly, our glycoconjugate‐derived cupric complex catalyzes the reactions among aldehydes, 2‐aminopyridines, and terminal alkynes under the solvent‐free condition to afford one‐pot synthesis of imidazo[1,2‐a]pyridines and 23 derivatives have been reported in good to excellent yields (53–93 %) using lower reaction time, temperature, and catalyst loading compared to other reports on similar reactions. Hence, our approach enhances the green methodology towards the catalytic synthesis of imidazo[1,2‐a]pyridine derivatives.

NbCl5 Functionalized Perlite: A Potent and Recyclable Catalyst for Synthesis of Pyrans

Niobium pentachloride functionalised perlite was prepared via a solid state dispersion technique, which was utilized as an efficient heterogeneous catalyst for the synthesis of pyrans. The immobilisation of NbCl5 over perlite was examined by Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Thermogravimetric analysis (TGA), scanning electron microscope (SEM) with energy dispersive spectra (EDS), and Brunauer, Emmett and Teller (BET) surface area measurements. The wt% of NbCl5-loaded perlite was optimized based on the adequacy with respect to the yield of the pyrans in various solvents. The recyclability of the catalyst was validated in synthesizing pyrans and the results marked its efficiency up to five runs. The efficacy of the NbCl5/perlite catalyst was found to be comparable and better with respect to the other heterogeneous catalysts reported. The structures of pyrans were confirmed by FT-IR, 1H and 13C NMR spectral techniques. The proposed recyclable heterogeneous NbCl5/perlite catalyst simplifies the protocol, and has minimal chemical waste, a lower reaction time and a high-yield.

Synthesis of a novel series of [1,5]-benzothiazepine-C-β-D-glycoside derivatives in a facile one-pot method and insight into their anti-oxidant properties

The development of seven-membered heterocyclic scaffolds, namely benzothiazepine, has gained much recognition in mild environmentally friendly conditions such as low temperature and short reaction time due to its vast medicinal pertinence. A novel class of [1,5]-benzothiazepine-C-β-D-glycosides was synthesized in a facile one-pot method from α, β-unsaturated-b-C-glycosidic ketones where the use of p-TSA had shown a better result. The β-anomeric forms of the C-glycosidic compounds were assigned from 1H NMR spectroscopy. Studies propose that the series of [1,5]-benzothiazepine-based β-C-glycosides showed moderate anti-oxidant activities with maximum inhibitory activity of 60%. The second generation [1,5]-benzothiazepine-β-C-glycoside (piperonal derivative) with 1,3-benzodioxole-substitution (compound 10d) especially showed excellent anti-oxidant characteristics at all concentrations ranging from 100 to 600 μg/mL.

An Alternative Approach for the Synthesis of Zinc Aluminate Nanoparticles for CO and Propane Sensing Applications

We implemented a simple and inexpensive aqueous sol-gel process to synthesize ZnAl2O4 nanoparticles to study its potential application as a gas sensor. Compared to traditional ceramic methods, the synthesis was conducted at lower temperatures and reaction times (5 h from 200 °C). The crystalline evolution of the oxide was investigated. The effect of the calcination temperature (200–1000 °C) on the crystallites’ size (16–29 nm) and the ZnAl2O4 powder’s surface morphology was also analyzed. Measurements confirmed the formation of bar-shaped granules (~0.35 μm) made up of nanoparticles (~23 nm). The surface area of the powders was 60 m2/g. Pellets were made from the powders and tested in sensing carbon monoxide and propane gases, showing a high sensitivity to such gases. The sensor’s response increased with increasing temperature (25–300 °C) and gas concentration (0–300 ppm). The oxide showed a higher response in propane than in carbon monoxide. We concluded that the ZnAl2O4 is a good candidate for gas sensing applications.

Decision-making from temporally accumulated conflicting evidence: The more the merrier.

How do humans evaluate temporally accumulated discrete pieces of evidence and arrive at a decision despite the presence of conflicting evidence? In the present study, we showed human participants a sequential presentation of objects drawn from two novel object categories and asked them to decide whether a given presentation contained more objects from one or the other category. We found that both a more disparate ratio and greater numerosity of objects improved both reaction time (RT) and accuracy. The effect of numerosity was separate from ratio, where with a fixed object ratio, sequences with more total objects had lower RT and lower error rates than those with fewer total objects. We replicated these results across three experiments. Additionally, even with the total presentation duration equated and with the motor response assignment varied from trial to trial, an effect of numerosity was still found in RT. The same RT benefit was also present when objects were shown simultaneously, rather than sequentially. Together, these results showed that, for comparative numerosity judgment involving sequential displays, there was a benefit of numerosity, such that showing more objects independent of the object ratio and the total presentation time led to faster decision performance.

Process integration of KOH/diatomite preparation and cyclopentanone self-condensation via ball-milling method

Cyclopentanone self-condensation is an attractive reaction for the production of sustainable aviation fuel. However, the catalysts used for this reaction are usually complex or time-consuming to prepare. The reaction also needs to be carried out at a high temperature and over a long reaction time. In this paper, an integrated process for catalyst preparation and self-condensation via the ball-milling method was proposed. Compared with the thermocatalytic method, this process can be implemented with higher product yield (98.6% vs. 85.0%), lower energy demand (0.43 kWh·g−1 vs. 1.31 kWh·g−1), less preparation and reaction time (3 h vs. 32 h) at room temperature. According to characterizations, the excellent catalytic activity of catalysts prepared by the ball-milling method can be attributed to two reasons: (i) Smaller particles are formed during the ball-milling process, which is more conducive to catalyst and reactant contact during the reaction; (ii) Less moisture is absorbed by the catalyst, which has a positive effect on catalytic activity.

Cortical Brain Perfusion and Cognitive Event Related Potentials in Patients with Psychomotor Retardation in Late Onset Depression.

Late onset depression is characterised by pronounced cognitive impairment, more somatic complaints and psychomotor retardation. Psychomotor slowing may be due to impairment in either motor or cognitive domain. Electrophysiology may be particularly convenient as a tool in studies of psychomotor retardation, as it can separate central cognitive processing from the motor processing. In this study we compared event related potentials (ERP) in the two groups of patients with late onset depression and psychomotor slowing as measured by reaction time (RT): a group of patients with lower RT was compared to a group with a higher RT. Twenty patients with late onset depression were included in the study after they had reached remission. Four weeks after reaching remission patients were reevaluated clinically using Hamilton Depression Rating Scale, Mini Mental State Examination, and with a computer version of the Stroop task. ERP, accuracy and RTs were simultaneously recorded. Both groups of patients aditionaly underwent a perfusion SPECT imaging. There were no differences between the short and long RT groups of patients in amplitudes of the late positive Stroop related potentials. The group of patients with longer RTs showed significant hyperperfusion in precentral gyrus, parietal regions, cuneus and hypoperfusion within insular, frontal, temporal and limbic (parahyppocampal gyrus and anterior cingulate) cortices, as well as cerebellum. We found no ERP differences between the two groups suggesting that although patients may differ on psychomotor retardation measured as RT, their cognitive abilities may be quite similar. Perfusion SPECT imaging however revealed a significant difference between them. This may be due to a process of compensation and applying different strategies to cope with cognitive impairment in the two groups.

Efficient synthesis of some novel pyrimido[4,5‐e][1,3]oxazine dione derivatives via one‐pot three‐component reaction under thermal and thermal microwave‐assisted conditions

AbstractConcise and attractive synthesis of a new class of pyrimido[5,4‐e][1,3]oxazine diones was attained with impressive yields, using a convenient and elegant condensation reaction between thiobarbituric acid and aryl glyoxals in the presence of N‐methyl urea in EtOH under thermal and thermal microwave‐assisted conditions. Some specific merits of the current procedure, include the availability of the starting materials, low reaction time, high reaction yield, operational simplicity, no harmful by‐products, and the high purity of the isolated products. Structures of all the freshly synthesized products have been deduced by their FT‐IR, 1H‐NMR, 13C‐NMR, and elemental analysis.

Odds of self-reported minor cycle crashes with conventional and electric assisted cycles adjusted for cycling frequency in Dutch and Belgian adults a retrospective study

BackgroundCycling for transportation and recreation is gaining in popularity, especially in older age groups. The rise in electric assisted cycles (EAC) may also have a role to play in this. With an increase in the number of cyclists comes an increase in the prevalence of cycle crashes. However, there is a lack of knowledge on EAC crashes and crash studies including cycle use data. An important question is also whether the high number of serious road injuries among older cyclists, is due to increased risk or more serious consequences in the event of a crash. Study aimTo compare the odds of reporting a cycle crash on a conventional (CC) against electrically assisted cycle (EAC), while controlling for age, gender, BMI, impairments while cycling, cycling frequency and region of residence. MethodsA 12-month retrospective cross-sectional survey-based study, including male and female cyclists aged 40+ years, was conducted in Belgium and the Netherlands. Socio-demographics, physical and mental impairments while cycling (such as lower reaction time), crash details and cycling frequency data were collected. Cyclists were grouped into CC, EAC or both (CC + EAC) based on the type of cycle they used during the study period. Logistic regression models were used to calculate the odds of reporting a cycle crash. Main and interaction effects were studied. Results1,919 cyclists were included in the data analysis (63.2 ± 11.1 years; 50% women). 319 (17% of the total sample) cyclists reported a crash in the previous 12 months, of which 36% were EAC crashes. Those reporting a crash were significantly younger compared to those not reporting a crash. The following significant main effects were observed: those cycling on an EAC had a higher odds of reporting a cycle crash compared to those cycling on a CC (OR = 1.41, 95% CI = 1.01–1.97); cyclists in the category average and high on mental impairments while cycling had a higher odds of reporting a cycle crash compared to those in the category low (OR = 1.72, 95% CI = 1.23–2.40 and OR = 3.49, 95% CI = 2.51–4.90, respectively); higher cycling frequency is related to higher odds of reporting a cycle crash (OR = 3.25, 95% CI = 2.25–4.90). A significant interaction effect was observed between age category and gender (OR = 1.93, 95% CI = 1.15–3.26). Post-hoc tests revealed that men in the younger age category (40–64 years) had the highest probability (18.95%) of reporting a cycle crash, whereas men in the oldest age category (65+ years) had the lowest probability (9.99%) of reporting a cycle crash. No significant difference between age categories in women was observed. ConclusionThis study indicates that within a cohort of middle aged and older adults living in regions with high to low cycling modal shares, cycle type, mental impairments while cycling, cycling frequency and region of residence play a significant role in the odds of reporting a (minor) cycle crash. Men in the age category 40–64 years have a significantly higher probability of reporting a cycle crash compared to men of 65+ years. Safety campaigns and instructions should pay particular attention to men in the age category 40–64 years and those with a mental impairment while cycling.

Development of a New Colorimetric, Kinetic and Automated Ceruloplasmin Ferroxidase Activity Measurement Method.

Ceruloplasmin plays an important role in the regulation of iron metabolism. Ceruloplasmin is an acute-phase protein known to have many metabolic effects. Its activity increases during infection, inflammation, and compensation of oxidation. In the current study, our aim is to develop a new method for the measurement of ferroxidase activity without requiring any chromogen. Venous blood samples were collected into serum separator tubes. Ferric iron ions formed by the enzyme ferroxidase were measured, both manually and fully automatically, at the 415 nm wavelength without using chromogen. These results were compared to conventional ferroxidase measurement methods and to the immunoturbidimetric ceruloplasmin measurement method. The detection limit of the new assay was 14.8 U/L. The upper limit of the linearity was 1380 U/L. Precision values were calculated for high, medium, and low levels of ferroxidase activity in serum pool. The coefficient of variation was <5% for each level. In the present method, chromogens are not used. With its considerably low cost and short reaction time, this method is able to provide fast results, can be performed easily, and makes accurate measurements.

Sustained Attention as Measured by Reaction Time Variability Is a Strong Modulator for the P600, but Not the N400.

The functional significance of the two prominent language-related ERP components N400 and P600 is still under debate. It has recently been suggested that one important dimension along which the two vary is in terms of automaticity versus attentional control, with N400 amplitudes reflecting more automatic and P600 amplitudes reflecting more controlled aspects of sentence comprehension. The availability of executive resources necessary for controlled processes depends on sustained attention, which fluctuates over time. Here, we thus tested whether P600 and N400 amplitudes depend on the level of sustained attention. We reanalyzed EEG and behavioral data from a sentence processing task by Sassenhagen and Bornkessel-Schlesewsky [The P600 as a correlate of ventral attention network reorientation. Cortex, 66, A3-A20, 2015], which included sentences with morphosyntactic and semantic violations. Participants read sentences phrase by phrase and indicated whether a sentence contained any type of anomaly as soon as they had the relevant information. To quantify the varying degrees of sustained attention, we extracted a moving reaction time coefficient of variation over the entire course of the task. We found that the P600 amplitude was significantly larger during periods of low reaction time variability (high sustained attention) than in periods of high reaction time variability (low sustained attention). In contrast, the amplitude of the N400 was not affected by reaction time variability. These results thus suggest that the P600 component is sensitive to sustained attention whereas the N400 component is not, which provides independent evidence for accounts suggesting that P600 amplitudes reflect more controlled and N400 amplitudes reflect more automatic aspects of sentence comprehension.

A novel Hercynite‐supported tetradentate Schiff base complex of manganese catalyzed one‐pot annulation reactions

The present study is the first report on the synthesis and catalytic performance of Hercynite nanoparticles capped with a novel Schiff base–manganese(II) complex brought from a synthetic procedure. The solid support and the catalyst were characterized using various analytical techniques. The characterization results suggest excellent dispersibility, stability, high Mn content under the catalyst surface, and small size of catalyst, which leads to excellent catalytic activity and selectivity. Moreover, the catalyst proved to be sustainable and recyclable for rapid synthesis of various chromene‐ and pyran‐annulated heterocycles under ambient conditions. The effect of various crucial catalytic parameters was investigated and optimized. The scope of the reaction was extended to various aryl aldehydes and keto–enol tautomeric pairs (2‐hydroxy‐1,4‐naphthoquinone or dimedone), and the corresponding 2‐amino‐3‐cyano‐4H‐chromene and 2‐amino‐3‐cyano‐4H‐pyran products were obtained with excellent yield (82–99%) and at low reaction time (10–115 min). Significantly, the catalyst indicated magnetic, cost‐effective, and nontoxic properties, which result in having high recycling efficiency (5 cycles).

Study of a Rechargeable Lithium-Ion Battery Based on a Copper Hexacyanoferrate Cathode

Rechargeable lithium-ion batteries are among the most promising battery technologies to meet energy conversion and storage requirements. However, this technology is still limited due to its high cost, which prevents its use on a large scale. Therefore, cheaper energy storage systems with long cycle life, high power/efficiency, and safety are in great demand and interest. Prussian blue analogs are promising candidates for use in large-scale energy storage applications due to their long-life cycles, high power density, and high energy efficiency [1]. Along with the change of the transition metal, some structural parameters and some fundamental properties of these compounds can be changed, affecting some parameters such as the battery's storage capacity.This work studied the electrochemical insertion of lithium ions into Copper Hexacyanoferrate (CuHCF). This compound was synthesized by a hydrothermal process using a factorial design for determining the significance variables, i. e., precursor concentrations, temperature, and reaction time, on the electrochemical performance of the battery. The samples obtained were characterized by FESEM, TEM, XRD, and TGA. The results show cubic structures with a high degree of crystallinity and an evident dependence of the crystallite size (50 - 140 nm) with the variation of the synthesis conditions. Finally, lithium-ion batteries were measured using a CuHCF cathode (theoretical charge 85.1 mAhg-1). The capacity values depended on the crystallite size, obtaining the best results in the synthesis under lower concentrations, reaction time, and temperature. This sample was submitted to deep charge/discharge cycles at a rate of C/20, where the capacity value was close to 60 mAhg-1 (right image). This demonstrates the influence of the crystallite size on the material's performance, managing to find the optimal synthesis conditions to maximize the battery capacity. References. [1] 1. Marzhana Omarova, Aibolat Koishybay, Nulati Yesibolati, Almagul Mentbayeva, Nurzhan Umirov, Kairat Ismailov, Desmond Adair, Moulay-Rachid Babaa, Indira Kurmanbayeva, Zhumabay Bakenov, Electrochim. Acta, 184 (2015) 58-63. Figure 1

Single‐catalyst reactions from depolymerization to repolymerization: Transformation of polyethylene terephthalate to polyisocyanurate foam with deep eutectic solvents

AbstractPolyisocyanurate (PIR) has been used as a flame retardant insulation material because of its improved thermal insulation and flame‐retarding effects due to its cyclic structure with an isocyanate trimer group. When a deep eutectic solvent (DES) is used as a catalyst, PET glycolysis produces bis(2‐ hydroxyethyl terephthalate) (BHET) and its derivatives. These recycled polyols react with isocyanate to form PIR foam (PIRF) in the presence of a physical blowing agent. DES‐based glycolysis is a low‐energy process with a relatively low temperature and short reaction time. In this study, a potassium‐based DES system was applied for the sequential depolymerization and repolymerization of waste PET into PIRFs. Potassium‐based DESs were used as hydrogen bond acceptors (HBAs), and ethylene glycol (EG), glycerol, and urea were used as hydrogen bond donors (HBDs). The PIRF was obtained through one‐pot depolymerization and repolymerization with a single‐catalyst DES system. All DES catalyst systems effectively decomposed PET; the PET conversion efficiency reached 95% after 2 h reaction. The recycled PIR was more thermally stable (approximately 26.9% limiting oxygen index (LOI) and approximately 68.8 W/g heat release rate (HRR)). This paper presents an environmentally friendly and robust upcycling process for the transformation of waste PET into PIRF.