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The development of highly selective homogeneous electron transfer reagents is highly desirable for synthetic chemistry. An isolable spirosilole tetra-anion described in this paper has been proved to be a promising soluble electron transfer reagent. The reduction of octaphenyl-1,1′-spirobisilole (1) with lithium resulted in the formation of the isolable spirosilole tetra-anion in good yield. The tetra-anion (2) has been characterized by nuclear magnetic resonance (NMR) and cleanly underwent electron transfer reactions with dioxygen, carbonyl groups, and transition metal halides to yield reduction products with the regeneration of 1.

Two N-heterocyclic carbene platinum complexes [PtMe2(NHC)], 1 and [Pt(TFA)2(NHC)], 2, in which, NHC = 1, 1′- methylene- 3, 3′- bis[(N-(tert-butyl) imidazol-2- ylidene] have been prepared and characterized using NMR spectroscopy and ESI-MASS spectrometry. Reactivity of these complexes toward hydrosilylation of some α,β-unsaturated ketones investigated by NMR spectroscopy. Dimethyl bis-NHC platinum(II) complex shows good performance in comparison with those observed for trifluoroacetate bis-NHC platinum(II) complex, 2 in which higher efficiency and selectivity obtained with dimethyl complex 1 as catalyst. Although, the 1,2-additon and 1,4-addition pathways are possible, regiochemistry of the products show a 1, 4- addition is preferred pathway for these reactions.

A novel methodology is proposed to identify the distribution of the intensity of the illuminant across a real‐world image; with this information, the image can be classified as a homogeneous or nonhomogeneous lighting source. A criterion is proposed for deciding whether the illumination in the tested image is homogeneous or nonhomogeneous. This criterion is based on well‐established methods that are dedicated to improving color characteristics and are commonly used to determine the color of the lighting source during a captured scene. The classification of homogeneous or nonhomogeneous illumination in real‐world images is implemented in the BSD500 database, and the results are compared with a manual classification of images—proposed under subjective criteria—by the authors; in this way, one can analyze how the lighting source affects the image. This procedure provides a classification methodology for real‐world image databases found in the scientific literature. [ABSTRACT FROM AUTHOR]

The intrinsic hydrophobic nature of polymer tubes limits their applications in biomedical and mechanical fields. In this paper, homogeneous hydrophilization on the inner surfaces of polytetrafluoroethylene tubes was realized by directly inserting a flexible atmospheric cold microplasma jet (FμPJ) into the tubes. The water contact angle, surface morphologies, and chemical compositions of the treated inner surfaces were investigated to characterize the plasma hydrophilization. Results demonstrated that the wettability of the inner walls of the tube was well improved and the wettability could be retained at a low value even after 30 days of storage. Notably, homogeneous hydrophilization was achieved along the axial and circumferential directions of the tube. The results indicated that FμPJ shows great potential for uniform inner surface modification of polymers tubes. [ABSTRACT FROM AUTHOR]

Multilayered Al sheets having alternative stacking of 2 N Al (99.21 wt.% purity, N is short for nine) and 4 N Al (99.993 wt.% purity, N is short for nine) with various layer thicknesses from 16 to 1 μm were fabricated by 6 to 10 accumulative roll bonding (ARB) cycles, followed by annealing. The effects of layer thickness and annealing treatment on mechanical properties were studied. In all samples, the grain sizes in the 4 N layers were larger than those in the 2 N layers due to the purity difference. The grain size and mechanical properties saturated after 6 ARB cycles, but the layer thickness gradually decreases with increasing cycles and accordingly, more homogeneous microstructures were obtained with higher cycles. After annealing, heterogeneous structures were retained in 6-cycle sample, while most homogenous structures were observed in 10-cycle sample. Yield-drop phenomenon widely observed in the homogeneous samples disappeared in the heterogeneous 6-cycle sample after annealing at 225 and 250 °C. [ABSTRACT FROM AUTHOR]

Kinetics of hydroformylation of camphene was investigated in the presence of [Rh(CO)2(acac)]/P(OPh)3 catalyst in a temperature range of 363–383 K. The influence of parameters such as stirring speed, camphene, catalyst, ligand concentrations, and partial pressures of H2 and CO on the activity and selectivity of the catalyst has been studied. The rate showed a first‐order dependence with respect to catalyst and camphene concentrations. The effect of partial pressure of hydrogen showed fractional order dependence. The plots of rate versus excess ligand, that is, (P(OPh)3) concentration and rate versus CO partial pressure passed through maxima and showed typical substrate/ligand inhibited kinetics. An empirical rate equation has been proposed and found to be in good agreement with the observed rate data. The kinetic parameters and activation energy were also evaluated. [ABSTRACT FROM AUTHOR]

Physical unclonable functions (PUFs) are hardware security primitives that are used for device authentication and cryptographic key generation. Standard XOR PUFs typically contain multiple standard arbiter PUFs as components, and are more secure than standard arbiter PUFs or feed-forward (FF) arbiter PUFs (FF PUFs). This paper proposes design of feed-forward XOR PUFs (FFXOR PUFs) where each component PUF is a FF PUF. Various homogeneous and heterogeneous FFXOR PUFs are presented and evaluated in terms of four fundamental properties of PUFs: uniqueness, attack-resistance, reliability and randomness. Certain key issues pertaining to XOR PUFs such as their vulnerability to machine learning attacks and instability in responses are investigated. Other important challenges like the lack of uniqueness in FF PUFs and the asymmetry in FPGA arbiter PUFs are addressed and it is shown that FFXOR PUFs can naturally overcome these problems. It is shown that heterogeneous FFXOR PUFs (i.e., FFXOR PUFs with non-identical components) can be resilient to state-of-the-art machine learning attacks. We also present systematic reliability analysis of FFXOR PUFs and demonstrate that soft-response thresholding can be used as an effective countermeasure to overcome the degraded reliability bottleneck. Observations from simulations are further verified through hardware implementation of 64-bit FFXOR PUFs on Xilinx Artix-7 FPGA. [ABSTRACT FROM AUTHOR]

The purpose of LTE-A technology is to provide high spectral efficiency, lower delay and stronger intercell interference control for a multi- user environment. The architecture of LTE basically contains E-UTRAN and evolved packet core. E-UTRAN is the combination of UE and ENodeB (enhanced node B) used to control the radio network. EPC provide end to end connection and backward capability with previous networks. Major entities included in EPC are P-GW, S-GW, HSS and MME. This new architecture fulfil the requirement of next-generation mobile networks for high connectivity and multiple type of networks. Heterogeneous network is one of them in which different power base stations like femtocell, picocell, and radio remote head deployed in a geographical area with in macrocell cell. It is one of the cost effective solution to provide high throughput and spectral efficiency and fairness for cell edge user. Deployment of femtocell improved the data rate and coverage in small regions like office, home, shopping mall and dense areas. Along with this an efficient fair sharing of resource allocation plays an important role in improving the performance of networks. This paper analysed the performance of round robin, resource fair, Max-throughput, best CQI and proportional fair LTE-A resource scheduling techniques on homogeneous networks. For heterogeneous networks a new cluster based proportional fair resource scheduling technique is proposed, which provides an efficient resource to the most sufferer user and improved fairness and cell edge user throughputs. In heterogeneous networks multiple femto cell were deployed in macro cell area. Access policies are applied on open and closed group. The performance is measured in terms of cell edge throughputs, peak throughputs, average throughputs, wideband SINR, spectral efficiency, and fairness index for homogeneous, heterogeneous networks and for user mobility. The performance result showed that Best CQI and MaxTP scheduler outperforms in throughput level and attains highest average cell throughput of 83 Mbps and UE average throughput of 20 mbps in homogeneous networks and approximately 43 Mbps in heterogeneous networks. Comparative result in heterogeneous network indicates that the proposed scheduler increases 2% gain in fairness and 1–1.89% gains in edge throughputs with respect to proportional fair scheduler and allocates 79% fair share resources among UE. Round robin scheduler delivered very poor throughput and fairness index in both homogeneous and heterogeneousnetworks. [ABSTRACT FROM AUTHOR]

N‐Salicylidene amino acid Schiff base sodium sulfonate salt, as a tridentate dibasic chelating ligand, was obtained from the common condensation of salicylaldehyde‐5‐sodium sulfonate with tyrosine (HPST). The internal formed ligand coordinated to Cu2+ ion in an aqueous media affording new Cu (II)‐complex (Cu‐PST), which characterized by various physico‐chemicals spectral tools. The mononuclear complex was evaluated as a homogeneous and heterogeneous catalyst in the (ep)oxidation protocols of 1,2‐cyclooctene and benzyl alcohol. Heterogeneously, Cu‐PST was immobilized on Fe3O4‐SiO2, as nanoparticles. The heterogeneous catalyst was characterized by infrared, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, energy‐dispersive spectroscopy, Brunauer−Emmett−Teller and magnetism. Homogeneously, the temperature, solvent and oxidant influences were examined in the catalytic reactions to realize the best reaction conditions. Cu‐catalyst exhibited better catalytic performance in the (ep)oxidation processes homogeneously than that in the heterogeneous phase at 80°C for 2 hr in acetonitrile. Reusability of the homogeneous catalyst was for a maximum of three times in the (ep)oxidation reaction, whereas the heterogeneous catalyst was active for six times. A mechanistic pathway was proposed for both catalysts, comparatively. [ABSTRACT FROM AUTHOR]

In this work, a novel homogeneous electrochemical aptasensor based on electrically assisted bond and tetraferrocene signal amplification was constructed for thrombin detection. Importantly, modification of the electrode is not necessary for this sensor, requiring only the construction of a simple and efficient probe. In addition, a brand new signal marker-tetraferrocene, containing four ferrocene molecules, was employed as a label to the terminal position of the probe. Compared with a single ferrocene moiety, tetraferrocene possesses a larger amplification signal for rapid detection of thrombin. In the detection of thrombin, the selected aptamer probe with a stem-loop structure was labeled with tetraferrocene at the 3′ terminal and thiol at the 5' terminal, respectively. Confinement of the thiol to the stem-loop structure of the probe, the ability of thiol to reach the surface of electrode lossed even with the aid of the applied potential. However, upon treatment with the target protein of thrombin the stem-loop structure opened, promoting rapid attachment of the thiol group to the electrode interface generating Au–S self-assembly with the action of potential-assistance. The electrochemical signal of tetraferrocene could be measured by differential pulse voltammetry (DPV), which was subsequently used for target quantitative detection. This strategy displayed a detection limit as low as 0.126 pM, and an inherently high specificity for the detection of a single mismatch. Moreover, it exhibited advanced specificity against common interfering proteins. Image 1 • Rapid detection of thrombin based on homogeneous strategy. • Tetraferrocene, a signal amplification marker including four ferrocene perssad, was first synthesized. • Sensitive electrochemical aptasensor was based on electrically assisted bond with detection limit reaching 0.126 pM. [ABSTRACT FROM AUTHOR]

The introduction of a simple triazole moiety on a terpyridine ligand in the complex [Ru(tpy)(bpy)(Cl)]+ ([1]+; tpy = 2,2':6',2''‐terpyridine; bpy = 2,2'‐bipyridine) gives rise to a suitable electrocatalyst for the reduction of CO2 to CO. The triazole group in [Ru(tpyaz)(bpy)(Cl)]+ {[2]+; tpyaz = 4'‐[4‐(tert‐butylphenyl)‐1H‐1,2,3‐triazol‐4‐yl]‐2,2':6',2''‐terpyridine} enables the complex [2]+ to bind with CO2 even at the one‐electron reduced state of the complex. Further 2nd‐electron addition after CO2‐coordination to the catalyst facilitates efficient CO2 reduction, based on cyclic voltammetry analysis. [ABSTRACT FROM AUTHOR]

Synthesized by phosphorus oxychloride and n‐butanol, tri‐n‐butyl phosphate from a three‐step esterification reaction has an extensive range of applications in industrial processes. Similarly, monobutyl chlorophosphate can be obtained rapidly by mixing n‐butanol and phosphorus oxychloride. In view of this, we investigated the kinetics of esterification of monobutyl chlorophosphate with a microchannel system composed of micromixer and coiled capillaries. The reaction started from mixing the phosphorus oxychloride solution and n‐butanol solution in a micromixer, with temperature and residence time in a delayed loop controlled, and then quenching the solution in a container with magnetic agitation. The rate constants for the esterification reaction of monobutyl chlorophosphate were determined to be within a temperature range of 298‐318 K. It was found that the reaction kinetics is second order with respect to monobutyl chlorophosphate concentration and first order to n‐butanol concentration. In our research, a kinetic model was established, the values of the pre‐exponential factor and the activation energy of the reaction were obtained. The reaction kinetic model can interpret the synthesis mechanism of phosphate esters well, thus playing a guiding role in process intensification of phosphate esters synthesis in the future. Additionally, our model is also valuable because it contributes to the establishment of a reaction kinetics network model for the cascade reaction to synthesize phosphate esters. [ABSTRACT FROM AUTHOR]

Glutathione‐protected Pd, PdAu and PdPt nanoparticles (NPs) show greatly increased reactivity and stability towards the hydrogenation/isomerization of allyl alcohol in a biphasic organic/aqueous solvent mixture compared to single‐phase alkanethiol‐protected Pd‐based NPs. NPs synthesized under aerobic conditions have higher activity compared to those synthesized under nitrogen, with the highest TOF of 676 mole product/mole metal/hour for 75 : 25 PdAu NPs at 20 mL/min H2 flow. 75 : 25 PdAu NPs prepared under nitrogen have a maximum TOF of 507 at 20 mL/min H2 flow, but can be recycled 4 times (9 times at 8 mL/min H2 flow). Ethyl acetate is a better organic phase solvent compared to dichloromethane and chlorobenzene in terms of TOF and recyclability. All of the NPs studied show >80 % selectivity for the isomer product (propanal). The branched, open structure of the glutathione and use of the biphasic solvent provides high catalytic activity, high selectivity, and easy removal of the products in the organic phase for good recyclability of the water‐soluble catalysts. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a simple, facile, and efficient one-pot synthesis of polymer–quantum dot nanocomposite films where nitrogen-doped graphene quantum dots (N-GQDs) were homogeneously dispersed in UV-curable, transparent polymer host matrix via the thiol–ene "click" reaction pathway. The highly fluorescent NOA–NGQD nanocomposite films exhibited strong hydrophobicity with water contact angle (>69°) owing to restructuring of the polymer chain networks. The various functional groups of the N-GQD surface, as carbonyl, amine, and hydroxyl groups, provided more interactive sites and low agglomeration to develop the strong electrostatic interactions between the NOA and N-GQDs, resulting in flexible NOA–NGQDs nanocomposites. Thus, obtained NOA–NGQD nanocomposites exhibited high transparency (>90%), low band-gap, and strong fluorescence spectral peak (>500 nm) after the homogeneous inclusion of N-GQDs in the NOA polymer matrix. This study paves the way to diverse applications of functionalized GQDs as well as transparent polymers for the development of hydrophobic polymer–QD nanocomposites by using UV catalyzed thiol–ene chemistry. Hence, as synthesized nanocomposite films would be widely applicable in flexible electronic display devices, light emitting diodes (LEDs), and optoelectronic applications. [ABSTRACT FROM AUTHOR]

We have studied two structurally related, water‐insoluble ruthenium complexes [RuII(tpy*)(phenCO2)](PF6) (1) (tpy*=5,4′,5′′‐tri‐tert‐butyl‐2,2′;6′,2′′‐terpyridine; phenCO2H=1,10‐phenanthroline‐2‐carboxylic acid) and [RuII(tpy)(dmphen)(Cl)](PF6) (2) (tpy=2,2′;6′,2′′‐terpyridine; dmphen=2,9‐dimethyl‐1,10‐phenanthroline, also known as neocuproine) and their electrocatalytic activity for CO2 reduction in acetonitrile and after immobilization on the reduced graphene oxide (rGO) in water (pH 7.2). Under homogeneous conditions (in CO2 saturated acetonitrile solution), characteristic major CO2 reduction waves indicate ∼280 mV lower overpotential upon changing the catalyst from 1 to 2. The higher CO2 electroreduction performance of 2 is also reflected on the heterogeneous rGO surfaces. [ABSTRACT FROM AUTHOR]

We have studied two structurally related, water‐insoluble ruthenium complexes [RuII(tpy*)(phenCO2)](PF6) (1) (tpy*=5,4′,5′′‐tri‐tert‐butyl‐2,2′;6′,2′′‐terpyridine; phenCO2H=1,10‐phenanthroline‐2‐carboxylic acid) and [RuII(tpy)(dmphen)(Cl)](PF6) (2) (tpy=2,2′;6′,2′′‐terpyridine; dmphen=2,9‐dimethyl‐1,10‐phenanthroline, also known as neocuproine) and their electrocatalytic activity for CO2 reduction in acetonitrile and after immobilization on the reduced graphene oxide (rGO) in water (pH 7.2). Under homogeneous conditions (in CO2 saturated acetonitrile solution), characteristic major CO2 reduction waves indicate ∼280 mV lower overpotential upon changing the catalyst from 1 to 2. The higher CO2 electroreduction performance of 2 is also reflected on the heterogeneous rGO surfaces. [ABSTRACT FROM AUTHOR]

These studies focused on polymer flooding for optimal recovery of heavy-oil. It was premised on a detailed reservoir simulation study using ECLIPSE and the polymer used was hydrolyzed polyacrylamide (HPAM). Water and polymer flooding cases were the scenarios considered. The water flooding case had its highest recovery with the "homogeneous case of low permeability" with a production total of 176412.3 sm³ (FOE=50.1 %). As for the polymer flooding cases, polymer concentrations in the range of 1 to 5 kg/m³ were tested. Polymer slugs with different concentrations at different injection times were injected for each case and the results were compared. The best polymer flooding case was with the use of HPAM of concentration 2.0 kg/m³ with 7 years of polymer injection followed by chase water injection. It had a recovery efficiency of over 84%. It also shows the most favorable reservoir pattern for polymer flooding in the heavy oil reservoir. [ABSTRACT FROM AUTHOR]

A sensor node in the wireless sensor network (WSN) has an inadequate energy, and it cannot be interchanged due to the arbitrary placement, so the objective is to extend the network lifetime. An inadequate energy becomes a crucial problem to solve energy efficiency in WSN. In this work, we propose a new Self-Organizing Cluster based Greedy best-first search Opportunistic routing (SOCGO) protocol for balanced energy routing. In our proposed work, the operation of work is divided into four stages for energy balanced routing. They are Sleep state, active state, guard state and death state. The residual energy consumed through the examining adjacent nodes is presented as an aspect to estimate the detection rate, and it can achieve through the novel approach named as hybrid K-means and Greedy best-first search algorithm. Furthermore, the presence of coverage holes pairs within WSN can be recovered through an Opportunistic routing algorithm. This method repairs the coverage hole pairs and improves the network lifetime. Then this proposed SOCGO protocol can be implemented in both the homogeneous and heterogeneous environment. Simulation outcomes deliberates that our proposed SOCGO algorithm attains enhanced performance regarding the network lifetime, throughput, energy consumption, average end to end delay and packet delivery ratio. [ABSTRACT FROM AUTHOR]

This study was set out to investigate the efficacy of homogeneous and heterogeneous pushed output based instruction on upper-intermediate EFL learner’ speaking complexity. To do so, 41 (17 males and 24 females) EFL learners were selected from University of Zabol based on the results of OPT. Then, they were put in control and experimental groups based on the predetermined criteria. Retelling and decision making tasks were used in the treatments of experimental groups while control group received placebo during 15 sessions, twice a week. Public versions of IELTS speaking test were used as pre/post-test. The results of Independent sample t-test indicated that experimental groups outperformed control group. On the other hand, statistical analyses showed no significant differences between male and female speech complexity. To sum up, the findings demonstrated the fruitful effects of collaborative pushed output activities on speaking sub-skills. Likewise, the results suggested the implementation of similar strategies in the development of male and female speaking dimensions. Based on the findings, it can be claimed that teacher preparation programs should put teaching speaking on their list of priorities and provide courses on effective strategies for the development of speaking dimensions through implementing the main tenants of pushed output hypothesis.

Ultrasonography is widely used to examine reproductive systems in chelonians. Previous studies have described how follicular size is associated with the reproductive stages of yellow-margined box turtles (YMBTs), but our understanding of follicular morphology remains limited. This study describes the different ultrasonographic appearances of preovulatory follicles of these turtles in Taiwan. Randomly selected 28 adult captive female turtles were examined under ultrasonography, weekly from November 2012 to November 2013. The females were divided into ovulatory and non-ovulatory groups with equal number coincidentally based on the whole-year ovulation records. The ovulatory group had significantly larger follicles than the non-ovulatory group (average size of largest follicle, 2 1. 9 ± 2. 1 5 mm versus 1 4. 5 9 ± 6. 7 4 mm; p < 0. 0 0 1). Across both groups, preovulatory follicles exhibited five different morphologies: previtellogenic, homogeneous, heterogeneous, atretic, and multilayered. The multilayered follicles were only observed in the ovulatory group during the late preovulatory (February) and early ovulatory periods (March), resulting in a significant correlation with ovulatory stage (p = 0. 0 1 6). During the preovulatory period (from December to February), homogeneous follicles were the predominant follicles in both groups. During the ovulation period, heterogeneous follicles were the main follicles, but only in the ovulatory group. Finally, atretic follicles were predominant in the non-ovulatory group during the early latent period (August). This study provides detailed ultrasonographic data clarifying the correlation between turtle follicular morphology and reproductive cycle. A better understanding of how such morphology is associated with reproductive stages should improve breeding programs in zoos and thus facilitate conservation efforts. [ABSTRACT FROM AUTHOR]

• Flame extinction and instability of n-decane are greatly suppressed by Co 3 O 4. • Co 3 O 4 -based catalysts improve the ignition performance of n-decane significantly. • The coupling effects between heterogeneous and homogeneous reactions are analyzed. • Small amount of PdO dopants can enhance the activity and stability of Co 3 O 4. • Adsorbed OH* radicals are key oxidants in the surface reactions over PdO/Co 3 O 4. Aiming to achieve efficient utilization of high-energy–density fuels in the promising portable power systems, self-sustained combustion of n-decane over Co 3 O 4 -based catalysts in a narrow quartz reactor was investigated. Chemiluminescence, gas chromatography and various physicochemical characterization methods were used in this study. The evidences suggest that Co 3 O 4 -based catalysts can significantly reduce the ignition temperature and broaden the flammability limits of n-decane. The heat release stored in the catalyst bed can help improve the flame stability, delay the flame extinction, and achieve auto-ignition without forced heating. Besides, great promotion of the catalytic performance of Co 3 O 4 spinel is achieved by doping with 6 wt% PdO. PdO/Co 3 O 4 catalysts exhibit higher activity and enhanced ability in effectual resistance toward deactivate than pure Co 3 O 4. Furthermore, the coupling of heterogeneous and homogeneous reactions of n-decane has been analyzed. It can be revealed that both the adsorbed and gaseous OH* radicals play greatly different roles when using different catalysts. These findings promote the use of heavy hydrocarbon fuels for energy supply and contribute to designing efficient Co 3 O 4 -based catalysts rationally. [ABSTRACT FROM AUTHOR]

[Display omitted] The primary focus of catalytic chemistry is the synthesis of valuable chemicals from cheaper and more abundant substrates. The main objective of catalytic processes is to achieve higher yields at affordable costs under environmentally friendly conditions. Under homogeneous conditions, the synthesized bimetallic Mn(II) complex with (2-benzoylbenzoic acid, bba) and N , N coordinated (2,2-bipyridine, bipy) ligands, [Mn 2 (μ 1,3 -(C 6 H 5)CO(C 6 H 4)COO) 2 (bipy) 2 ] . 2ClO 4 is shown to be an active catalyst for the oxidation of monoterpenes (thymol and carvacrol), using TBHP under mild reaction conditions. The structure of the complex was characterized by single-crystal X-ray diffraction. The six-coordinated Mn(II) centers bridge in a coordination pattern due to the monodentate bonding mode of the carboxylate oxygen atoms of benzoylbenzoate anion. The selectivity of the Mn-catalyst was measured to be 100 % for thymol and carvacrol to thymoquinone. A simple, effective and selective Mn(II)/TBHP/Monoterpene/CH 3 CN catalyst system was used for the oxidation of thymol (TOF = 2000 h−1, in 15 min) and carvacrol (TOF = 667 h−1, in 45 min.) into a valuable product, thymoquinone (TQ), in acetonitrile at 80 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] • Successful hydrogenation with readily available RuCl 3 · xH 2 O/1,10-phenanthroline. • High functional group tolerance and applicable for gram-scale reactions. • Hydrogenation of lignocellulosic biomass-derived substrates (e.g., vanillin, 5-HMF, and eugenol) • Selective hydrogenation of alkenyl group in linoleic acid methyl ester. Hydrogenation of organic compounds with molecular hydrogen is an atom economic reaction and plays a key role in chemical synthesis. Here, we report the hydrogenation of carbonyl compounds to alcohols as well as alkenes to alkanes with easy-to-handle reagents under 10 bar hydrogen pressure. The hydrogenation reactions are executed with readily available RuCl 3 ·xH 2 O/1,10-phenanthroline and show high catalytic efficiency in the presence of other reactive functional groups (e.g., halogens and hydroxyl) under mild reaction conditions. Moreover, the chemoselectivity and robustness of the Ru catalytic system found their merit in the hydrogenation of lignocellulosic biomass-derived substrates (e.g., vanillin, 5-HMF, and eugenol) including linoleic acid methyl ester, affording the corresponding products in good to high yields. Density functional theory (DFT) calculations were carried out in conjunction with the Laplacian of electron density and natural bond orbital (NBO) analysis to unravel the mechanistic insights into the hydrogenation of the carbonyl compounds. [ABSTRACT FROM AUTHOR]

All spaces are assumed to be separable and metrizable. Ostrovsky showed that every zero-dimensional Borel space is σ -homogeneous. Inspired by this theorem, we obtain the following results: • Assuming AD , every zero-dimensional space is σ -homogeneous, • Assuming AC , there exists a zero-dimensional space that is not σ -homogeneous, • Assuming V = L , there exists a coanalytic zero-dimensional space that is not σ -homogeneous. Along the way, we introduce two notions of hereditary rigidity, and give alternative proofs of results of van Engelen, Miller and Steel. It is an open problem whether every analytic zero-dimensional space is σ -homogeneous. [ABSTRACT FROM AUTHOR]

[Display omitted] • Continuous flow homogeneous nitration of 2,4-Difluoronitrobenzene was established. • The effect of mixing on the nitration reaction process was analyzed by dimensionless number. • Compared to batch reactors, microreactors greatly reduce nitration reaction time. • Kinetic model of the homogeneous nitration reaction was developed. In this study, we first experimentally demonstrated that the homogeneous nitration reaction process in capillary T-micromixers was greatly influenced by the limitations of mixing. Therefore, to improve the mixing effectiveness, we investigated the intensification of liquid mixing in the heart-shaped microreactor. Compared with the capillary T-micromixer, the mixing effectiveness in the heart-shaped microreactor was improved by three orders of magnitude, resulting in a conversion rate of 98.5 % and a reduction in residence time by two orders of magnitude compared to batch reactors. Furthermore, we have established a kinetic model that eliminates interphase mass transfer resistance and verified its accuracy by comparing the calculated values with the experimental ones. The mixing properties in the microreactor were revealed using the Damköhler number, Peclet number, and the mixer effectiveness. These findings contribute to the development of nitration reactions by highlighting the advantages of microreactors in this area and offer guidance for potential applications within the chemical industry. [ABSTRACT FROM AUTHOR]

The reactions between chlorobenzene(CB) and ozone have been studied comprehensively in this paper. Chlorobenzene is a commonly found chlorinated aromatic volatile organic compound(VOC), and its emission into the atmosphere can cause harm to the ecosystem and human health. The frequent occurrence of mineral particles from sandstorms exerts a significant influence on the atmospheric chemistry of the troposphere. Mineral particles are abundant in SiO 2 and Al 2 O 3 content. Therefore, we investigated the homogeneous and heterogeneous reaction processes of CB and ozone in the atmosphere by using density functional theory (DFT) method at the M06-2X/6–311++g(3df,2p)//M06-2X/6–31+g(d,p) level. The atmospheric fate, reaction rate and toxicity evaluation of CB ozonation were studied in the gas-phase section. Toxicity evaluation results showed that ozonation of CB could effectively reduce its toxicity. For the heterogeneous process, we simulated three types of SiO 2 clusters and nine types of (Al 2 O 3)n clusters, and studied the configurations of CB adsorbed on the cluster surfaces. We found that adsorption of CB on the SiO 2 clusters was achieved through hydrogen bonding, while adsorption of CB on the Al 2 O 3 clusters was achieved through both hydrogen bonding and metal bonding. The energy for CB adsorption on the (Al 2 O 3)n cluster surface was higher than that for the Si x O y (OH) z cluster surface, and both types of clusters exhibited efficient adsorption of CB. As the Si x O y (OH) z clusters grew larger, the rates for the reactions between O 3 and CB increased. CB travelled long distances along the Al 2 O 3 clusters, leading to an extended influence range. [Display omitted] • The reaction mechanism of CB reacting with O 3 in homogeneous and heterogeneous were studied. • Toxicity assessment showed that ozonolysis effectively reduced the ecotoxicity. • The Al 2 O 3 clusters have a stronger adsorption effect on CB compared to the SiO 2 clusters. • The environmental risks may increase due to the promotion of Al 2 O 3 to the studied reactions. [ABSTRACT FROM AUTHOR]

In this paper, we derive a closed-form expression of the tail probability of the aggregate discounted claims under homogeneous, non-homogeneous and mixed Poisson risk models with constant force of interest by using a general dependence structure between the inter-occurrence time and the claim sizes. This dependence structure is relevant since it is well known that under catastrophic or extreme events the inter-occurrence time and the claim severities are dependent.