Energy Reduction Research Articles

An Intermittent Fasting Intervention for Black Adults Can Be Feasibly Implemented in Black Churches: A Cluster Randomized Controlled Pilot Study

BackgroundIntensive lifestyle interventions, including modest reductions in daily caloric intake (ie, continuous calorie energy reduction [CER]), are recommended by US national professional health organizations (eg, American Heart Association). However, they are less effective in Black communities. A burgeoning literature has reported the promise of intermittent fasting (IF) as an alternative strategy for weight loss. However, IF studies have been conducted with White participants predominately and provided participant resources not readily available in real-world situations. ObjectiveWeight-loss and weight-related outcomes of a scalable (ie, able to be widely disseminated and implemented) IF intervention developed with and for Black adults were compared with a CER intervention for the purpose of determining IF’s feasibility (ie, initial effectiveness, adherence, and acceptance) in a Black community. DesignA cluster randomized controlled pilot study was conducted. Participants/settingA total of 42 Black adults with a body mass index (calculated as kg / m2) ≥25 were recruited from 5 Black churches (3 IF and 2 CER) in Western New York State from September 2021 to May 2022. Participants were free of medical conditions that might have contraindicated participation in a weight-reduction program and other factors that might affect weight loss. InterventionsCommunity health workers delivered the 6-month, 16-session, faith-based IF and CER interventions. Main Outcome MeasuresThe primary outcome was feasibility, consisting of initial effectiveness on body weight (ie, percent body weight lost from baseline to 6-month follow-up), adherence, and acceptability. Statistical analyses performedDescriptive statistics and linear mixed models accounting for within-church clustering were used. A baseline covariate corresponding to the outcome variable was included in the model. Intent-to-treat analysis was used. ResultsThere was statistically significant weight loss within both arms (IF: –3.5 kg; 95% CI –6 to –0.9 kg, CER: –2.9 kg; 95% CI –5.1 to –0.8 kg) from baseline to 6-month follow-up. Compared with CER, IF led to significantly lower daily energy intake (414.2 kcal; 95% CI 55.2 to 773.2 kcal) and fat intake (16.1 g; 95% CI 2.4 to 29.8 g). IF may result in lower fruit and vegetable intake (–103.2 g; 95% CI –200.9 to –5.5 g) and fiber intake –5.4 g; 95% CI –8.7 to –2 g) compared with CER. Participants in the IF arm completed a mean (SE) of 3.8 (1.4) more self-monitoring booklets compared with those in the CER arm (P = .02). Participants reported high levels of satisfaction with the program. ConclusionsAn IF intervention developed with and for Black adults can be feasibly implemented in Black churches. Larger studies need to be conducted to ascertain the extent IF can serve as a viable weight-loss alternative to CER interventions in Black communities.

Geometry optimization in the schematic design phase of low-energy buildings for all European climates through genetic algorithms

The ongoing transition towards resilient and energy-efficient cities highlights the design of new buildings as a critical concern. With the increasing urbanization in Europe and the concurrent need for energy reduction and decarbonization, it is crucial to address energy efficiency in the construction sector, as by the recently adopted European Energy Performance of Building Directive. In this context, the article focuses on the role of geometry optimization in the schematic design phase of low-energy buildings, by considering it among different European climates. Indeed, this study aims to propose a multi-objective optimization approach (using a genetic algorithm) to optimize the “genes” of the building, e.g., shape, proportions, orientation and window-to-wall ratio of residential buildings in the early design phase, to cut off a significant portion of energy consumptions. The objective is thus to minimize heating and cooling energy needs based on the best combination of the above-mentioned genes. The research investigates optimal solutions across various European climates based on the Köppen-Geiger classification, comparing the results for 19 European cities with varying climate. The findings confirm that the energy needs of buildings are strongly influenced by the climate conditions of their location. The study, which comprehends almost 250.00 different configurations, assesses, as expected, the strong effect of climate conditions on the energy needs and highlights the cross-shaped buildings as the best performing in 17 over 19 sites investigated. The optimal solution for each site leads to total energy needs that are comprised between 4.58 kWh m-2 y-1 in Porto and 19.84 kWh m-2 y-1 in Goteborg, with an average across all cities of 12.45 kWh m-2 y-1. The research provides valuable insights for professional in the construction sector, aiding them in making informed decisions during the schematic design phase to achieve low-energy buildings that are adapted to specific climates.

Hardening properties and microstructure of 3D printed engineered cementitious composites based on limestone calcined clay cement

Comparison of three-dimensional (3D) printing and cast methods on the mechanical properties of cementitious materials is the basis for intelligent construction development. To achieve this, a series of experiments including the uniaxial tensile, compressive, flexural and interlayer bonding tests of mould-cast and 3D printed (3DP) specimens are conducted to investigate the effects of different preparation technologies on the microstructure and hardening properties of limestone calcined clay cement (LC3) based engineered cementitious composites (ECC). Results indicate that the tensile strength and strain capacity of the printed LC3-ECC decrease by 16.6%–22.7 % and 43.3%–54.6 % compared to the cast specimens, while it still possesses a strain capacity of 2 % and multiple cracking behaviour. The compressive and flexural properties of the printed LC3-ECC both show significant anisotropy, the maximum values of which are observed in the Z- and Y- directions, respectively. The interlayer bonding strength increases by 54.3%–91.9 % at 28 d compared to that at 7 d due to the hydration of LC3. The pore structure of the printed LC3-ECC is denser than that of the cast LC3-ECC, with more regular arrangement and finer size of pores. The macro-micro properties correlation analysis proves the better comprehensive performance of printed LC3-ECC relative to casted LC3-ECC, as well as reveals the relationship between pore structure and anisotropy. In terms of material sustainability, 3DP-LC3-ECC has a significant reduction in energy and carbon emissions compared to typical M45-ECC, contributing to the environmental development.

Bond behaviour of prestressed basalt textile reinforced concrete

Innovative Textile Reinforced Concrete (TRC) composites, although holding a significant potential, usually have poor performance under serviceability conditions. Addressing this limitation requires applying innovative techniques, such as prestressing, to utilise its potential fully. However, successful design and application of prestressing require a comprehensive understanding of the prestressing effect across scales, including the textile-to-matrix bond behaviour. To address this need, this study investigated the influence of key parameters such as prestressing level, prestressing release time and matrix age on the bond behaviour of basalt textile reinforcement. Test results show a significant influence of prestressing level and release time on textile-matrix bond behaviour. A 1-day prestressing release time resulted in a 25 % increased stiffness with only a 5 % peak load reduction followed by a further 13.7 % increase in the pull-out energy when the prestressing level was 13 %. At 35 % prestress level, 1-day released samples showed a significant reduction of 48.4 % in the peak load and 76 % reduction in the debonding energy. The positive effect of prestressing on the bond behaviour became more evident at prolonged release durations. The 7-day release samples showed a 17.4 % increase in the peak load at both prestress levels. Meanwhile, at 35 % prestress level, 34 % further increase in the debonding energy was observed. The obtained data are then utilised for providing indications on the effect of prestressing on saturated crack spacing of TRC components.

Exploring the nonlinear optical characteristics of supersalt-decorated graphyne via DFT analysis: unveiling quantum insights into light-matter interaction

In this comprehensive study, we explore into the nonlinear optical (NLO) properties of graphyne (GRY) and its compounds decorated with a super salt (OLi3BeF3), namely GRY@SS1, and GRY@SS2) using the rB3LYP/6−31G(d,p) DFT method. Our findings reveal a substantial enhancement in the electron transfer properties of decorated compounds compared to the pristine GRY surface. This enhancement is evidence by the reduction in the bandgap energies (Eg) from 3.52 eV to 1.68 eV and remarkable boost in maximum absorption ( λmax) from 372.66 to 807.73 nm. Noteably, GRY@SS2 exhibits a significant increase in linear polarizability ( α0 ) (538.18 au), first hyperpolarizability ( β0 ) (3872.76 au), and second hyperpolarizability ( γ0 ) (1.00 × 106) due to reduced excitations energies compared to the GRY ( α0 = 448.61, β0 = 0.14 and γ0 = 5.97 × 105 au). NBO charges show that electrons are transferring from the dopant (supersalt) to the GRY sheet. Furthermore, Non-covalent interactions (NCl), iso-surface, infrared (IR), 1H NMR, and 13C NMR studies have been conducted to provide insights into the nature of interactions, vibrational frequencies, and structural-functional aspects of GRY and GRY@SS1, and GRY@SS2. According to TD-DFT calculations, all compounds demonstrate superior vertical ionization potential, UV–vis absorbance, HOMO–LUMO characteristics, as well as interaction energies. Our results underscore the potential of these compounds as valuable NLO materials, particularly highlighting the promising prospects of GRY@SS2.

Structural analysis, relaxor-ferroelectric behavior and optical properties of Mn3+-doped CaBi3NdTi4O15 synthesized via hydrothermal technique

In this study, the synthesis of the Aurivillius Ca1-xBi3+xNdTi4-xMnxO15 (CBNTMx), where x is 0, 0.2, and 0.4, was carried out using the hydrothermal technique. The X-ray diffraction (XRD) data showed that the polar orthorhombic structure in space group of A21am was adopted by all powder samples. All samples possessed anisotropic plate-like particle shapes, and the particle size increased with increase in x value. The phase transition temperature (Tm) is decreased by the ionic substitution owing to the decrease in orthorhombic distortion reflected by the reduction of orthorhombicity. Relaxor-ferroelectric behavior was observed for CBNTM0.4 because of its strong frequency dispersion, while CBNTM0 and CBNTM0.2 only showed a diffused-phase transition (DPT) indicated by the broad dielectric constant at the transition temperature (Tm). The electrical conductivity exhibited an enhancement at higher x value since the ionic substitution with acceptor Mn3+ ions introduced the charge carrier in the lattice. Similarly, the reduction of optical band gap energy from 3.43 eV for the parent CBNTM0 to 2.75 eV and 2.71 eV for CBNTM0.2 and CBNTM0.4, respectively, was described as the contribution of the lower energy level of Mn 3d orbital than that of Ti 3d in the conduction band and also the less distorted structure.

Comparison of mathematical and supervised machine-learning models for ductile-to-brittle transition in bcc alloys

This study focuses on modelling Ductile-to-Brittle Transition (DBT) curves using various mathematical and supervised machine learning models. Charpy impact energy values are converted to normalized energy values to account for reductions in upper-shelf energy. The research introduces a saturation parameter in mathematical models to capture these variations and examines the influence of alloying elements, microstructure, and neutron irradiation on DBT behaviour in nuclear structural materials. Detailed analyses reveal how fitting parameters vary with these factors and demonstrate that mathematical models’ fitting parameters generally align with observed DBT curve trends. The predictive capabilities of these mathematical models are also compared with those of supervised machine learning models, highlighting the strengths and limitations of each approach in modelling DBT behaviour. An explainable approach is used for interpretation of machine learning models and it is shown that this approach can be effectively used for the influence of various independent parameters on impact energy.

An Insight into the Impact of Nano CuCo2O4 Doping on the Optical and Dielectric Performance of PMMA/Carbon Nanoparticles

In the present study, novel functional properties were achieved for polymethyl methacrylate (PMMA) through loading with carbon nanoparticles (CNPs) as well as varying quantities of CuCo2O4 nanoparticles. The blends obtained were subjected to different characterization techniques. Extensive investigations of different optical properties were carried out, covering linear and nonlinear optical properties. After the incorporation of CNPs/CuCo2O4 in the host polymer matrix, the absorbance, reflectance and refractive index exhibited improvements, while continuous reductions in both direct and indirect optical band gap energies were observed. Significant improvements in the linear and nonlinear optical parameters were observed with increasing CuCo2O4 doping levels. Dielectric measurements provided insights into the impact of CuCo2O4 content on the ac conductivity, energy density, dielectric properties, and electric modulus across all blends. The sample doped with 1.5 wt% exhibited the highest dielectric constant. In conclusion, the optical and dielectric properties of the PMMA/CNPs/x wt% CuCo2O4 blends make them promising candidates in optoelectronics and photocatalysis applications.

Phase separation behavior and CO2 absorption kinetic analysis of DETA/DEA/DMAC biphasic absorbent

Lower regeneration energy and superior cyclic capacity have enabled biphasic absorbents great potential in the area of flue gas CO2capture. The liquid film mass transfer coefficient(kL) is a vital parameter in the development of absorbents with efficient CO2 absorption mass transfer performance, while the phase separation behavior of biphasic solutions could be an essential factor for the absorption mass transfer and the stability of absorber. However, systemic kinetic research towards biphasic absorbents, especially the impact of phase separation behavior, is limited. In this study, a typical amide-based biphasic absorbent diethylenetriamine(DETA)/diethanolamine(DEA)/N, N-dimethylacetamide(DMAC) which has achieved great reduction in regeneration energy, was selected as the subject of kinetic investigation in a wetted wall column. The CO2 overall mass transfer coefficient(KG) of DETA/DEA/DMAC exceeded other biphasic solvents, blended amine solution, and 40% K2CO3 solution, with 3 times that of 40% K2CO3 solution. Moreover, various operational conditions including absorption temperature, gas flow rate, and water content of solution were taken into account to build a multiple-condition kinetic mechanism to offer guidance for biphasic absorbents. Furthermore, phase separation behavior was revealed as the main blame for the deterioration in the liquid film chemical mass transfer process of biphasic solvents in the CO2 absorption process, resulting in the kL of DETA/DEA/DMAC before phase separation decreased by 75.3% at the phase separation stage. Therefore, it is crucial to ensure that the CO2 loading of the solution entering absorber is lower than the phase separation point in applications. After phase separation, DETA/DEA/DMAC split into the organic and aqueous phases, the kL of the aqueous phase gradually exceeded that of the organic phase as CO2 loading increased for its higher chemical enhancement factor(E).

New approach for zero energy industries via integrating energy management and renewable energy system: Enviro-economic investigation

The building sector stands as the world’s predominant energy consumer and major contributor of CO2 emissions. In the recent years, the Zero Energy Building (ZEB) concept has been gaining traction as a solution to this challenge. However, while the concept has been primarily used for residential buildings where it has shown promising results, its application in the industrial sector has not been extensively explored. So, the current study proposes a sustainable approach to achieve zero energy for an industrial site using PV system. The approach is applied on a manhole cover manufacturing company located in Alexandria, Egypt. Firstly, an energy audit is conducted to identify the energy consumption patterns and energy waste sources in the facility. Next, an energy management where various energy saving measures are implemented to optimize energy use in the facility follows. Then, an 850kWp grid connected PV array is designed and sized using PVsyst simulation tool to supply the remaining net annual energy consumption of the industrial site. The results show that the energy management reduces the entire facility’s energy consumption by about 20 % with a yearly saving of energy, cost, and CO2 emission reduction of 425.3MWh, 22,536$, and 850.4 tons, respectively. Moreover, the proposed PV system proves its reliability and efficiency to supply slightly more than the remaining facility energy needs of 1257.74 MWh/year thus achieving zero energy status. With an investment of 211,480 USD, a payback period of about 4 years is estimated with a Life Cycle Emission of 18,444 tons CO2 reduction. The study shows that achieving Zero Energy Industries (ZEI) is technically and economically feasible by combining energy management and Renewable Energy Systems (RES). Besides its contribution to SDG’s 7 and 13, the study elaborates the significance of implementing ISO 50001 towards energy efficient practices in industrial sites thus providing valuable insights and recommendations to various stakeholders and policy makers.

Gravity train of variable mass

The gravity train is a virtual vehicle that travels in a tunnel across Earth, and its motion due to only gravity is a simple harmonic oscillator. It can run at a constant velocity by appropriately exhausting fuel. In this case, the train obeys the equation of motion for a variable mass system. We discuss the mass and energy reduction of the gravity train during travel and find the optimal conditions for economical travel. This study is suitable for university students in physics classes.

Ultraviolet–Visible-near infrared induced photocatalytic H2 evolution over S-scheme Cu2-xSe/ZnSe heterojunction with surface plasma effects

Localized surface plasmon resonance (LSPR) effect plays a crucial role in the field of solar energy utilization. In this work, we successfully prepared a Cu2-xSe/ZnSe S-scheme heterojunction with a broad-spectrum response using the hot-injection and low-temperature water bath method. Importantly, we demonstrated that the photothermal effect induced by the LSPR of nonstoichiometric Cu2-xSe can significantly improve the slow kinetics of water splitting, resulting in an apparent activation energy reduction from 50.1 to 28.7 kJ·mol−1. This improvement is responsible for achieving the highest photocatalytic H2 evolution rate of 63.6 mmol·g−1·h−1 over 2.7 % Cu2-xSe/ZnSe under the wavelength ranged from 200 to 2500 nm, which is 3.4 and 5.6 times higher than that of ZnSe and Cu2-xSe, respectively. Furthermore, the composite exhibits a remarkable H2 production rate of 0.108 mmol·g−1·h−1 under near-infrared spectroscopy (800<λ<2500 nm), while ZnSe shows limited capability in H2 releasing. Additionally, Cu2-xSe/ZnSe demonstrates distinct photocurrent response when λ > 800 nm. The enhanced performance in H2 evolution can be attributed to the synergistic effect of LSPR-induced light absorption and S-scheme heterojunction, which not only expands the light absorption range to the near-infrared region but also facilitates hot electron injection, charge carrier separation and transfer, leading to a faster surface reaction kinetics. This study provides an effective approach for designing a broad-spectrum light responsive non-precious metal-based photothermal-assisted photocatalytic system.

Identifying enhancement of double slope solar still performance by adding water cooling to walls

The object of this research is a double-slope solar still with the addition of water cooling on the wall (DSSS.WCW). The issue with solar stills is that the temperature of the cover glass is quite high, which consequently reduces the rate of evaporation. Methods to reduce the cover glass temperature involve water cooling, by flowing water and spraying it onto the cover glass. Both of these methods have been shown to reduce the temperature of the cover glass, but they still require additional energy and can decrease the solar radiation energy received by the absorber plate. This research proposes using a water cooling method on the wall that does not require additional energy and can prevent a reduction in the solar radiation energy received by the absorber plate. Experimental and theoretical research was conducted to study the effect of using DSSS.WCW. The results showed a 13.48 % reduction in the cover glass temperature, consequently increasing the temperature difference between the fins and the cover glass by 9.82 °C. The increase in temperature difference resulted in a 13.82 % increase in freshwater productivity theoretically by 2.80 kg/hour and a 13.10 % increase experimentally for the DSSS.WCW by 2.58 kg/hour. In addition, there was a theoretical increase in energy efficiency of 22.29 % and an experimental increase of 22.82 %, along with an increase in exergy efficiency of 15.71 %. The implementation of water cooling on the wall has been shown to enhance the efficiency of the double-slope solar still. In addition, the water cooling method on the wall does not reduce the solar radiation energy that can be received by the absorber plate and does not require additional energy. The results of this research can be applied in remote islands in Indonesia, particularly during the dry season

Approximate Computing Based Low-Power FPGA Design for Big Data Analytics in Cloud Environments

As cloud computing continues to evolve, the demand for scalable and energy-efficient infrastructure to handle extensive applications becomes paramount. Traditional transistor scaling and microprocessor design methods no longer suffice to meet the growing scale of cloud usage. This research explores the potential of approximate computing (AC) as an innovative solution to these challenges, particularly in high-demand computational settings. AC, known for its ability to make controlled accuracy trade-offs, is identified as a key strategy for improving both the performance and energy efficiency of cloud infrastructure, with a focus on low-power Field-Programmable Gate Array (FPGA) designs. This paper introduces novel methodologies that harness the strengths of AC, emphasizing its application in neural-based and machine-learning techniques for energy-efficient solutions. By targeting the performance of AC, especially in varied application domains and complex data mining scenarios, we propose two groundbreaking approaches that significantly enhance computational speed and reduce energy consumption. Our empirical analysis demonstrates notable improvements over existing techniques, highlighting the effectiveness of AC in optimizing cloud infrastructure. The proposed model on FPGA through cloud computing attains substantial elevation rates by 89 % and energy reduction by 122%, which had been good outcomes. This study not only confirms the benefits of integrating AC with low-power FPGA designs for cloud environments but also sets a new benchmark for future research in achieving more sustainable and efficient cloud computing via VLSI FGPA design analysis solutions.

Energy recovery of four-wheel hub motor driven vehicle in steering-braking condition

The factors that affect the efficiency of braking energy recovery is a crucial and worthy research problem for the four-wheel hub motor driven (FWHMD) electric vehicle (EV). This paper presents an energy classification statistical method by integrating the direct current (DC) of the power battery and considering the efficiency of the permanent magnet synchronous motor (PMSM). According to the characteristics of DC, the energy recovered and consumed by the motor during regenerative braking is divided into total recovered energy, net recovered energy and dissipated energy. Then, the influence of steering resistance on braking energy recovery of the steering braking is analyzed by using the proposed energy statistical method and combining Carsim and Matlab/Simulink co-simulation. Firstly, a closed-loop coupling model combined with the PMSM and vehicle dynamics is established. Secondly, the braking energy recovery only the PMSM engaged is simulated for different brake strengths under steering-braking conditions, also the stability of the vehicle is analyzed and the recovery energy is counted. Lastly, the energy recovered is compared with the recovery energy by longitudinal braking under the same braking strength. The results show that the energy recovery of the steering regenerative braking conditions with braking strengths of 0.1 and 0.2 is 4.10% and 1.90% less than that of the longitudinal braking conditions with the same braking strengths, respectively, and the steering resistance is constant. The reduction of the recovery energy is only related to the braking time. Meanwhile, the research in this paper provides a reference significance for the research of braking energy recovery strategies for FWHMD vehicles.

Development and performance evaluation of active insulation systems using solid-state thermal switches

Traditional building envelopes have passive insulation systems that cannot respond to dynamic changes in the environment. An Active Insulation System (AIS) consists of Active Insulation Materials (AIMs) that dynamically vary the thermal conductivity of the insulation system. Several researchers have evaluated the impact of AIS on building thermal and energy performance by using simulation tools. Up to 70% savings in annual heating and cooling energy and significant reductions in peak demand have been predicted for some climates with wall systems employing AIS. However, materials and assembly development still need a cost-effective product that achieves the required performance. In this study, we present the process of developing an AIS that we will install in a test hut for its performance evaluation. Minimum performance criteria of the AIS system are developed based on R-low/R-high ratio, required time and efficiency to switch states, and cost estimates. The following steps during this study are creating the concept to meet the requirements, predicting the performance via simulations, developing the experimental setup for bench-scale testing, and finally, constructing a full-scale wall assembly and monitoring the performance when exposed to environmental chamber tests. The selected approach uses off-the-shelf products to create an AIS that can switch R-value between 0.98 ft2·°F·h/BTU (0.173 m2·K/W) and 5.81 ft2·°F·h/BTU (1.02 m2·K/W) and have a switching time of less than one minute between R-high and R-low.

Sensitivity to heat and mass transfer correlations of the model for an evaporative condenser

Evaporative condensers have established themselves in refrigeration plants for food process and storage owing to the combination of air and water cooling, with an overall reduction in energy (pumping) and fluid (water) consumption. Given the steep rise of electricity prices, the need to develop conduction strategies at the plant level which are less energy-intensive has driven the need for models to carry out simulations of the new strategies without actually impacting normal plant operations. This paper describes the development of a distributed-parameter model of an evaporative condenser with fill-pack, based on Merkel’s pioneering works on evaporative cooling. Several correlations are available for the heat and mass transfer coefficients, but none that satisfies the operating conditions of the case at hand, yet they are the most critical set of parameters for the model, therefore a sensitivity study has been carried out, to ascertain which combinations of transport coefficients out of a total of 288 would yield a total cooling power closest to the value declared by the manufacturer for a real-life evaporative condenser under rating conditions. This work demonstrates the applicability of the correlations examined, and also twenty of the examined combinations allow the model to reach a good agreement with the reference data (within ±5%). Further, the distributed-parameter structure of the model allows highlighting the reasons for good or bad performance of the correlations by determining the spatial distribution in the cooling coil and fill-pack of quantities such as moist air enthalpy and water temperature. The model and methodologies are a little cost-intensive in terms of computational time and can be applied to the study and design of any similar piece of equipment.

Effects of tree crown height on the flow hydrodynamics and tsunami energy reduction around the coastal forest

Effects of tree crown height on the flow hydrodynamics and tsunami energy reduction around the coastal forest

Stacked Si Nanosheets Gate-All-Around Transistors with Silicon-on-Nothing Structure for Suppressing Parasitic Effects and Improving Circuits’ Performance

We propose a novel silicon-on-nothing (SON) structure with an air sub-fin for suppressing the parasitic channel effects on stacked Si nanosheets (NS) gate-all-around (GAA) transistors and a systematic investigation is carried out by 3D TCAD simulation. The SON structure could be fabricated using a backside selective etching technique. The proposed SON NSFETs with a designed air sub-fin structure demonstrates systematic advantages, including 40% off-state current reduction in the sub-channel, and 51.37% promotion for on-off current ratio (ION/IOFF) and 7.04% reduction in effective capacitance. Moreover, there is approximately 21.62% power reduction under the same frequency, and about 16.30% energy reduction under the same delay in 17-stage ring oscillators (ROs). The SON NSFETs-based 6T-SRAM exhibits decreased read time and write time by 14.66% and 67.53%, respectively, compared with those of the conventional GAA NSFETs-based 6T-SRAM.

Defect induced Raman shifts and bandgap engineering in layered SnSe2+δ bulks

In the context of the extensive application prospect of two-dimensional (2D) chalcogenides, we synthesized layered SnSe2+δ bulks with defects employing a hybrid chemical vapor transport-melt approach. Both the Eg and A1g Raman characteristic peaks in SnSe2+δ are dominated by cubic anharmonicity, coupled with nonlinear temperature dependencies below 140 K. Notably, the reduction in phonon energy observed in these vibrational modes can be ascribed to defect-mediated Raman scattering, irrespective of deficient or excess Se defects. However, the lower consistency in the Raman shifts of the in-plane Eg vibrations compared to the out-of-plane A1g modes suggests that the defects predominantly entail the absence of Se atoms and the substitutions of Sn by Se, delineating a continuum of Se-deficient and Se-enriched compositions. Furthermore, Se defects induce the contraction of the indirect bandgaps, facilitating a transition from medium to narrow bandgap semiconductors in SnSe2+δ, which underscores the tunable nature of the bandgaps through the incorporation of Se defects. These discoveries present an avenue for bandgap engineering and foster a deeper comprehension of the phonon and thermal properties of layered chalcogenides for further advanced technologies.