Reduction Route Research Articles

HIV Prevention in Syringe Service Programs Since the Start of COVID-19: Where Do We Go From Here?

This narrative review addresses post-2020, specific, complex challenges for use of and adherence to pre-exposure prophylaxis (PrEP) for HIV prevention among out-of-treatment people who use drugs (PWUD) at syringe services programs (SSPs). The COVID-19 pandemic and its associated changes to the provision of healthcare have significantly impacted HIV prevention, especially for PWUD. Through a synthesis of literature and clinical experience, we (1) characterize the operational changes imposed by the pandemic on SSPs that shaped the current HIV prevention landscape; (2) describe three levels of current challenges for PWUD, including consumer attitudes, non-medical and medical provider attitudes, and structural and scalability barriers; (3) characterize current models for PrEP in SSPs; and (4) offer practical recommendations for HIV prevention in harm reduction programs. PrEP is a highly effective prevention tool if taken as prescribed. It has been enthusiastically promoted by members of the research, public health and provider communities. Despite its efficacy, PWUD struggle to engage with the PrEP care continuum. We highlight opportunities to advance HIV prevention for PWUD by enhancing tailored, whole-person approaches that may set aside PrEP in favor of other risk reduction routes. For most PWUD who receive services at SSPs, PrEP is a single tool and not realistic until other social and structural determinants of health are addressed.

Effect of intermittent water flow on biodegradation of organic micropollutants in the hyporheic zone.

Water scarcity in the Mediterranean area has increased the number of intermittent rivers. Recently, hyporheic zones (HZ) of intermittent rivers have gained attention since a substantial part of the stream's natural purification capacity is located within these zones. Thus, understanding the flow dynamics in HZs is crucial for gaining insights into the degradation of organic micropollutants. A lab-scale study using column experiments was conducted in an attempt to elucidate the environmental processes accounting for the biodegradation capacity of the HZ under flow intermittency. A mixture of six compounds including pesticides (chloranthraniliprole, fluopyram and trifloxystrobin) and pharmaceuticals (venlafaxine, amisulpride and paroxetine) spiked at 1μg/L level was used for degradation kinetic studies and at 1mg/L for transformation products identification using suspect/non-target liquid chromatography high-resolution mass spectrometry approaches. The experiments lasted 60 days, divided into two 14-day phases: one before and one after a 5-week desiccation period. Bacterial community was charaterized by high-throughput DNA sequencing. The results suggested that intermittent flows stimulated the biodegradation of three compounds namely fluopyram, trifloxystrobin and venlafaxine, showing a large range of biodegradation profiles in batch water/sediment testing system according to OECD 308 tests. Biodegradation rate enhancement was ascribed to the occurrence of additional transformation routes after the desiccation period of river sediment, with the formation of new transformation products reported for the first time in the present work. 16S rDNA sequencing revealed that the desiccation period favored the growth of nitrifying and denitrifying bacteria which could partially explain the emergence of the new transformation pathways and most specifically those leading to N-oxide derivatives. Identification of transformation products also revealed that reductive transformation routes were relevant for this study, being dehydrogenation, dehalogenation, ether bond cleavage and sulfone reduction into sulphide important reactions. These results suggest that the intermittent flow conditions can influence the HZ biodegradation capacity.

Strong Component‐Interaction in N‐doped 2D Ti3C2Tx‐Supported Pt Electrocatalyst for Acidic Ethanol Oxidation Reaction

AbstractDesigning electrocatalysts with the selective C─C bond breaking in ethanol electro‐oxidation is of interest as an efficient strategy to accelerate the large‐scale applications of direct ethanol fuel cells (DEFCs).Pt nanoparticles (NPs) are herein on N‐doped 2D Ti3C2Tx MXene via two‐step synthesis steps including NH3‐assisted hydrothermal and NaBH4‐assisted ethylene glycol reduction routes. With the selective C─C bond breaking, the as‐obtained 16 wt.% Pt/N‐Ti3C2Tx catalyst exhibits 435.35 mA mgPt−1 mass activity and 0.83 mA cm−2 specific activity, being 1.26‐ and 1.77‐fold increase compared to those of commercially available 20 wt.% Pt/C (346.21 mA mgPt−1 and 0.47 mA cm−2). This originates from the advantages of unique 2D structures and the strong interplay between Pt NPs and nitrogen‐doped Ti3C2Tx. Also, the Pt/N‐Ti3C2Tx shows superior CO‐poisoning resistance and long‐term stability for the acidic ethanol electro‐oxidation reaction (EOR). This work demonstrates the potential of heteroatom‐doped Ti3C2Tx MXenes to increase the C1 pathway selectivity and the catalytic performance of Pt‐based electrocatalysts in DEFCs.

Evaluation of three different drugs administered through intraligamentary route for reduction of intraoperative pain of symptomatic irreversible pulpitis in mandibular molars – A randomized triple-blind single-center clinical study

Abstract Introduction: Managing intraoperative pain while initiating root canal treatment necessitates the use of supplementary injection techniques. Aim: The study sought to assess and compare the anesthetic efficacy of 0.5% bupivacaine and 50 mg/ml tramadol hydrochloride versus 2% lignocaine administered as supplemental intraligamentary injection as an adjuvant to an inferior alveolar nerve block (IANB) for mandibular molars with symptomatic irreversible pulpitis (SIP) and normal apical tissues during access cavity preparation. Materials and Methods: Two hundred and two individuals with mandibular molars diagnosed with SIP with normal apical tissues and exhibiting moderate-to-intense pain were given 2 ml of IANB containing 2% lignocaine and 1:80,000 epinephrine. The Visual Analog Scale (VAS) was used to record intraoperative discomfort. Individuals who scored more than 5 on the VAS were deemed to need further anesthesia. The intraligamentary medication was given to 99 of these patients after they were randomly assigned to 3 groups (2% lignocaine, 0.5% bupivacaine, and 50 mg/ml tramadol). VAS score was again recorded. If the patient reported no pain during the opening of the access, it was deemed a success. The post hoc Tukey’s test, paired t-test, and one-way analysis of variance were the statistical methods used to examine the data. Results: Maximum reduction in pain was in bupivacaine followed by lignocaine and tramadol (P < 0.05). Subgroup analysis using post hoc Tukey’s honestly significant difference test showed a maximum difference between bupivacaine and tramadol (1.273, P > 0.05) (95% confidence interval [CI]), followed by lignocaine and bupivacaine (−1.182, P < 0.05) (95% CI) and lignocaine and tramadol (0.091, P > 0.05) (95% CI). Conclusion: Bupivacaine was most effective in reduction of intraoperative pain when used as an intraligamentary drug during access cavity preparation followed by lignocaine. Tramadol was the least successful drug for achieving effective pulpal anesthesia.

A Low Temperature Calciothermic Reduction Approach for the Synthesis of LaB6 Powders

In this work, we report the synthesis of a polycrystalline LaB6 powders with a uniform morphology by a low-temperature metallothermic reduction route using calcium as a reductant. The processing methodology and heat treatment parameters are optimized based on thermodynamic estimates in order to favour the reaction kinetics and for complete formation of LaB6 powders with highest purity. The synthesised powder was subjected to comprehensive characterization studies. X-Ray Diffraction (XRD) revealed the complete formation of LaB6 compound without any traces of reactants. Scanning Electron Microscopy (FE-SEM) along with chemical mapping shows the morphology and elemental distribution of LaB6 powder. X-Ray Photoelectron Spectroscopy (XPS) results show the futuristic peaks with photon energies that are assigned to the core levels of the La and B without significant impurities whereas the Fourier transform infrared (FTIR) spectrum indicates an apparent presence of La-B bonds at 1045.4 cm−1, 585.5 cm−1, and at 463.1 cm−1.

Operando FTIR Characterization of Interphases from Organosulfur Electrolytes in High Voltage Lithium-Ion Batteries

The widespread adoption of renewable energy storage technologies like electric vehicles and grid storage largely relies on the improvements of the energy density of the batteries inside those devices. Lithium-ion batteries (LIBs) are typically used for these applications due to their high energy density,[1] but the operating voltage of LIBs is limited by the electrochemical stability windows of the electrolyte. Resistive interphase layers form as a result of the breakdown of electrolyte molecules and limit LIB cycling stability. However, there is significant difficulty in the study and characterization of both the components and structure of the electrode-electrolyte interphases formed via electrolyte degradation.[2] Traditional characterization techniques provide information on what the interphase layers look like after cell disassembly, but sample preparations are difficult and destructive.[3] Therefore, it is crucial to develop in operando techniques to better understand the relationship between the interphase layers and battery performance.In this work, we develop a custom surface-enhanced infrared absorption spectroscopy in the attenuated total reflectance mode (ATR-SEIRAS) setup for in operando studies of the solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI) in organosulfur electrolyte systems. Organosulfur molecules are potential components for high voltage LIBs due to their excellent performance.[4] We apply our custom ATR-SEIRAS setup to study ethyl methyl sulfone (EMS) containing electrolytes and propose possible reduction routes with the help of ex situ and postmortem characterization techniques. We study both SEI and CEI formed and correlate favorable interphase components with contributing molecules to identify important functional groups for novel molecular design. The work provides an opportunity to elevate our understanding of currently elusive electrochemical phenomena like the structure-reactivity relationships of SEI and CEI, and why certain sulfone systems outperform other formulations. Furthermore, it will provide molecular design principle for electrolyte systems in high performing and high voltage LIBs.References S. Chu, Y. Cui, and N. Liu, Nat. Mater., 16, 16–22 (2017).H. Wan, J. Xu, and C. Wang, Nat. Rev. Chem., 8, 30–44 (2024).A. Dopilka, Y. Gu, J. M. Larson, V. Zorba, and R. Kostecki, ACS Appl. Mater. Interfaces, 15, 6755–6767 (2023).M. A. Dato et al., Adv. Energy Mater., 2303794 (2024).

Polarized electric field-mediated graphitic carbon nitride-based S-scheme heterostructure for efficient photocatalytic removal of bisphenol A

Tuning interface charge transfer is considered as a feasible way to promote electron migration and separation in heterojunction system, but the role of in-plane electron behavior in single phase has received little attention. Here, a carboxyl functionalized graphitic carbon nitride (CCN) coupled PbBiO2Br (PBOB) S-scheme heterostructure is elaborately designed for investigation. Compared with pristine CN/PBOB, although the existence of carboxyl group weakens the built-in electric field strength of CCN/PBOB (ΔΦ = 0.44 eV), the formed polarized electric field (µ = 3.18 Debye) is conducive to the pre-separation of photogenerated electrons and holes in CCN, thereby improving interface charge transfer. In addition, the introduced carboxyl group can also serve as an O2 adsorption site to enhance its activation, and generate reactive oxygen species (ROS) through a two-step single-electron O2 reduction route. Thus, the optimized CCN/PBOB exhibits excellent photocatalytic ROS generation ability, which can remove 88.7 % of bisphenol A and significantly reduce the acute toxicity of the formed intermediates. This work provides a new perspective for the development of advanced heterojunction photocatalyst by regulating in-plane/interface charge dynamics, and helps to fully understand the pollutant detoxification/degradation process initiated by molecular oxygen activation.

Impact of graphene oxide reduction route over its performance in symmetric aqueous supercapacitors and lithium-ion negative electrodes

Carbon-based materials are recognized for their practical and multifunctional applications in a huge diverse of energy storage devices. Given the attractive properties and versatility of graphene-based materials over other carbon-based materials, graphene oxide (GO) and its derivate reduced graphene oxide (rGO) have become more popular. Three different rGOs were obtained through distinct reduction routes: chemical, hydrothermal, and microwave-assisted. rGOs were examined to identify their structural change, oxygenated functional groups (OFGs), thermal stability, and defects over their structures such as mixed sp2-sp3 domains. DFT calculations were carried out to study the PDOS of each rGO. The degree of reduction was considerably higher for the microwave-assisted rGO and hydrothermal rGO compared to chemical rGO, and the synthetic route also controlled the main OFGs. The electrochemical response of the synthesized rGOs was evaluated for symmetric supercapacitors (aqueous electrolytes) and for Li-ion storage (organic electrolytes). The improved behavior of hydrothermal rGO in aqueous electrolytes was related to the higher wettability provided by the protonation/deprotonation of OFGs at the expense of an increment of diffusion-controlled processes. Meanwhile, the improved behavior of microwave-assisted rGO in carbonate-based electrolytes was related to the higher grade of graphitization/number of sp3 domains among the synthesized rGOs.

Photocatalytic Semi-Hydrogenation of Acetylene to Polymer-Grade Ethylene with Molecular and Metal-Organic Framework Cobaloximes.

The semi-hydrogenation of acetylene in ethylene-rich gas streams is a high-priority industrial chemical reaction for producing polymer-grade ethylene. Traditional thermocatalytic routes for acetylene reduction to ethylene, despite progress, still require high temperatures and high H2 consumption, possess relatively low selectivity, and use a noble metal catalyst. Light-powered strategies are starting to emerge, given that they have the potential to use directly the abundant and sustainable solar irradiation, but are ineffective. Here an efficient, >99.9% selective, visible-light powered, catalytic conversion of acetylene to ethylene is reported. The catalyst is a homogeneous molecular cobaloxime that operates in tandem with a photosensitizer at room temperature and bypasses the use of non-environmentally friendly and flammable H2 gas feed. The reaction proceeds through a cobalt-hydride intermediate with ≈100% conversion of acetylene under competitive (ethylene co-feed) conditions after only 50 min, and with no evolution of H2 or over-hydrogenation to ethane. The cobaloxime is further incorporated as a linker in a metal-organic framework; the result is a heterogeneous catalyst for the conversion of acetylene under competitive (ethylene co-feed) conditions that can be recycled up to six times and remains catalytically active for 48 h, before significant loss of performance is observed.

Synergistic hardening in a dual phase high‐entropy (Hf,Nb,Ta,Ti,Zr)C–(Hf,Nb,Ta,Ti,Zr)B2 ultra‐high temperature ceramic

AbstractA dual phase high‐entropy (Hf,Nb,Ta,Ti,Zr)C–(Hf,Nb,Ta,Ti,Zr)B2 ultra‐high temperature ceramic was synthesized using a single step boro‐carbothermal reduction route. The synthesized powder was densified by spark plasma sintering at 2000°C, resulting in complete solid solution formation and a relative density of ≈99%. The dual phase ceramic was 43 vol% high‐entropy carbide and 57 vol% high‐entropy boride. The grain sizes were 0.85 ± 0.34 µm for the carbide and 0.87 ± 0.33 µm for the boride with minimal residual oxide (0.2 vol%) detected in the microstructure. The resulting composition had a higher microhardness than the individual boride and carbide ceramics across the range of testing loads with maximum hardness of 47.5 ± 4 GPa at a load of 0.49N. The high hardness is attributed to the minimum residual oxide, submicron grains, favorable carbide‐to‐boride ratio, homogeneous metal distribution within the phases, uniform microstructure, and synergistic dual phase hardening.

Unveiling the Brønsted acid mechanism for Meerwein–Ponndorf–Verley reduction in methanol conversion over ZSM-5

The conversion of methanol over zeolites offers a sustainable alternative for fuels and chemicals production. However, a complete understanding of the competing reaction pathways, particularly those leading to C-C bond formation, remains elusive. This work presents a novel mechanism for selective methanol conversion in ZSM-5 zeolites, involving a Brønsted acid site (BAS)-mediated Meerwein–Ponndorf–Verley (MPV) reduction pathway. Employing a multidimensional solid-state NMR spectroscopy combined with isotopic labeling and theoretical calculations, we identify this pathway for acetaldehyde reduction with methanol, directly contributing to ethene formation. This mechanism, involving carbenium ion intermediates like 1-hydroxyethane or 1-methoxyethane ions, contrasts with the well-established Lewis acid-catalyzed MPV process. Based on reactant adsorption modes, we propose two distinct reaction routes for BAS-MPV reduction, bridging the gap between direct and hydrocarbon pool mechanisms in methanol conversion. We further demonstrate the applicability of this pathway to acetone, highlighting its broader role in the early stages of the reaction.

Constructing boosted charge separation for efficient H2O2 production and pollutant degradation by highly defective ZnIn2S4/ carbon doped boron nitride

Solar-driven photocatalytic production of H2O2 as a promising environmentally-friendly approach has been applied as a chemical reagent and for enhancing photocatalytic remediation. However, this process is still limited by unsatisfactory efficiency and hard separation of photogenerated charge carriers. Herein, we design a dual pathway to improve hydrogen peroxide production by establishing a 2D/2D heterojunction between carbon-doped boron nitride (BCN) and defective zinc indium sulfide (ZIS). The introduction of multiple vacancies and dopants at the interface successfully promoted the interfacial charge transfer and peroxide generation. The Z-scheme heterojunction establishes a built-in electronic field, facilitating continuous electron accumulation and depletion, thereby inducing band bending. As a result, the optimized BCN/ZIS-30 composite (>420 nm wavelength) exhibits 925 μmol/g/h in pure water with no other additions and advances this production to 2006.1 μmol/g/h (2 times as defective ZIS and 12.1 times as BCN) under the existence of isopropanol and aeration. Mechanism investigation indicated that H2O2 is generated via a two-step electron reduction route and water oxidation reaction. The generated H2O2 successfully constructs a self-photo-Fenton system by forming hydroxyl radicals. Accompanied by strong oxygen activation ability, the photo-Fenton system also exhibits rapid degradation of antibiotics with 95 % elimination in 60 minutes. The practical applicability of this photocatalyst was demonstrated through real water remediation tests, exhibiting its effectiveness in removing antibiotics, COD, and total ammonia nitrogen, highlighting its potential for practical water treatment applications. This work provides a novel idea on constructing heterojunction materials for energy saving and water remediation.

Adsorption and Catalytic Reduction of Nitrogen Oxides (NO, N2O) on Disulfide Cluster Complexes of Cobalt and Iron-A Density Functional Study.

The reactivity of nitrogen oxide, NO, as a ligand in complexes with [Fe2-S2] and [Co2-S2] non-planar rhombic cores is examined by density functional theory (DFT). The cobalt-containing nitrosyl complexes are less stable than the iron complexes because the Co-S bonds in the [Co2-S2] core are weakened upon NO coordination. Various positions of NO were examined, including its binding to sulfur centers. The release of NO molecules can be monitored photochemically. The ability of NO to form a (NO)2 dimer provides a favorable route of electrochemical reduction, as protonation significantly stabilizes the dimeric species over the monomers. The quasilinear dimer ONNO, with trans-orientation of oxygen atoms, gains higher stability under protonation and reduction via proton-electron transfer. The first two reduction steps lead to an N2O intermediate, whose reduction is more energy demanding: in the two latter reaction steps the highest energy barrier for Co2S2(CO)6 is 109 kJ mol-1, and for Fe2S2(CO)6, it is 133 kJ mol-1. Again, the presence of favorable light absorption bands allows for a photochemical route to overcome these energy barriers. All elementary steps are exothermic, and the final products are molecular nitrogen and water.

Construction of Ru/MnO–Mn7C3/N-doped carbon sheets for boosting electrocatalytic hydrogen generation

Suffering from their low conductivity, Mn-base oxides are commonly inactive in H–OH activation. Generally, tailoring the coordinate environment of materials could induce variation in the atomic arrangement and further influence their chemical activity. Herein, we propose a feasible strategy to mediate the electronic structure of Mn-based oxides by facile hydrothermal method and thermal reduction route. Compared with MnO2 sheets, the as-synthesized Ru/MnO–Mn7C3/N-doped carbon sheets (Ru/MnO–Mn7C3/NC) exhibit the higher activity for both acidic (73 mV) and alkaline water reduction reaction (44 mV@10 mA/cm2). Benefitting from unique structures, Ru/MnO–Mn7C3/NC sheets show the better freshwater/seawater oxidation reactivity, exceeding RuO2. The strong interaction of MnO–Mn7C3 heterostructures, Ru, and N-doped carbon endows Ru/MnO–Mn7C3/NC with the good freshwater and seawater dissociation performance, outperforming most of the reported Mn-based oxides.

Platinum/Platinum Sulfide on Sulfur-Doped Carbon Nanosheets with Multiple Interfaces toward High Hydrogen Evolution Activity.

Platinum (Pt)-based materials are among the most competitive electrocatalysts for the hydrogen evolution reaction (HER) due to suitable hydrogen adsorption energy. Due to the rarity of Pt, it is desirable to develop cost-effective Pt-based electrocatalysts with low Pt loading. Herein, Pt/PtS electrocatalysts on S-doped carbon nanofilms (PPS/C) have been successfully fabricated through a precursor reduction route with a complex of Pt and 1-dodecanethiol (1-DDT) as the precursor. The PPS/C achieved at 400 °C (PPS/C-400) exhibits excellent HER performances with an ultralow overpotential of 41.3 mV, a low Tafel slope of 43.1 mV dec-1 at a current density of 10 mA cm-2, and a long-term stability of 10 h, superior to many recently reported Pt-based HER electrocatalysts. More importantly, PPS/C-400 shows a high mass-specific activity of 0.362 A mgPt-1 at 30 mV, which is 1.88 times of that of commercial 20% Pt/C (0.193 A mgPt-1). The introduction of sulfur leads to the formation of PtS, which not only reduces the content of Pt but also realizes the interface regulation of Pt/PtS, as well as the doping of carbon. Both regulations make the resulting catalyst have abundant active centers and rapid electron transfer/transport, which is conducive to balancing the adsorption and resolution of intermediate products, and finally achieving great mass-specific activity and stability. The research work may provide ideas for designing effective Pt-based multi-interface electrocatalysts.

A novel asymmetric superwetting filter prepared by easily mass-produced strategy for high-efficient and switchable water/oil filtration

All-purpose materials with on-demand oil/water separation property have received broad attention recently. Herein, a filter paper (FP)-based filter with asymmetric wettability was designed and fabricated via simple combination of liquid phase reduction route with symmetry adhesion method. The fabricated filter exhibits underoil superhydrophobic (UOSHP) and underwater superoleophobic (UWSOP) property. Especially, the good underliquids lyophobicity is still maintained after tape peeling and corrosive, organic solvents treatments. By fixing the hydrophobic (HO) side of filter facing up, the water/light oil mixtures and oil-in-water (O-in-W) emulsions can be highly efficient separated, and the water/heavy oil mixtures and water-in-oil (W-in-O) emulsions are able to be separated with the HI side facing up. The separation efficiencies for water/oil mixtures and oil/water emulsions are higher than 98% and 99.1%, respectively. The study offers a new idea for the preparation of asymmetric superwetting materials with good stability and on-demand water/oil separation capability.

Already at the minimum? Narratives of energy-use reduction in Finnish households

To combat the global problem of unsustainability, absolute reductions in energy use are needed, particularly in the Global North. There is an urgent need for a better understanding of the possible routes for reduction that go beyond abstracted technological solutions or efficiency improvements, as well as a need for a deeper insight into how the potential for reduction is currently framed. We use a citizen survey on perceptions of energy-use reduction as a means of exploring the perceived possibilities for reduction. Four ‘narratives of energy-use reduction’ that circulate among the public are identified: no reduction; price-enabled reduction; technology-enabled reduction; and competence-enabled reduction. We argue that these interlinking narratives are informative in understanding how change is understood amidst the bundle of practices related to energy-use reduction. They highlight the meanings related to energy use and allow us to explore the understandings of how the potential for energy-use reduction is positioned in society, particularly in regard to the notion of minimum consumption. Our findings are useful in providing a more nuanced understanding of the (de)constitution of energy use, and they contribute to identifying possibilities for steering energy use by providing insight into the general understandings of the current levels of energy use.

Synthesis of TaB2-TaC nanocomposite powders by a boro-carbothermal reduction route

This paper introduces the boron/carbon thermal reduction reaction, represented by the equation 2Ta2O5+ B4C + 11 C = 2TaB2 + 2TaC + 10CO (g), as a novel reaction pathway for synthesizing TaB2₋TaC composite powders. Subsequently, the SPS technique is employed for the fabrication of TaB2-TaC composite ceramics via sintering. The article begins by elucidating the fundamental process of this reaction and constructing a phase diagram through thermodynamic calculations. The experimental results demonstrate that adjusting the synthesis temperature and the proportion of the boron source in the raw materials enables effective control over the ratio of the two phases within the composite materials, allowing the TaB2 phase content to be tailored within the range of 38.1–60 %. Moreover, elevating the synthesis temperature and increasing the proportion of the boron source effectively mitigate the C,O impurity content in the composite powders and facilitate the TaB2 step-growth process. It is noteworthy that the hardness of TaB2-TaC composite ceramics sintered at 2000°C using the optimized complex-phase powder as the precursor reaches 21.7±0.5 GPa, and the fracture toughness attains 5.2±0.2 MPa⋅m1/2.

Synthesis of MeBICAAC Supported Si(III) Radicals and a Silylone via Reduction Route From MeBICAAC-Si(IV) Precursors.

Past one decade has witnessed a tremendous growth in the field of carbene stabilized low-valent silicon compounds unravelling very exciting properties of these molecules. Herein, we have employed a bicyclic (alkyl)(amino)carbene, (MeBICAAC) to explore the low-valent chemistry of silicon. The reduction of bicyclic (alkyl)(amino)carbene-SiCl4 complex, [(MeBICAAC)SiCl4] (1) with KC8 afforded low-valent Si complexes, including Si(III) radical [(MeBICAAC)SiCl3] (2) and a complex with silicon center in a formal zero-valent state, [(MeBICAAC)2Si] (3). Similarly, the reduction of in-situ generated MeBICAAC adduct of Me2SiCl2 with one equivalent of KC8 led to the formation of [(MeBICAAC)SiMe2Cl] (4) complex having an unpaired electron. These complexes have been characterized by IR, UV-Vis., NMR, HRMS, EPR and their solid-state structures were also elucidated by single crystal X-ray crystallography. Further, DFT calculations revealed the lower energy singlet state for complexes 1, 3 and doublet state for complexes 2, 4.

Numerical Analysis on the Quantitative Separation of Different NOx Formation and Reduction Routes during MILD Oxy-Coal Combustion with the Improved Nitrogen Chemistry Model

Numerical Analysis on the Quantitative Separation of Different NO_<i>x</i> Formation and Reduction Routes during MILD Oxy-Coal Combustion with the Improved Nitrogen Chemistry Model