Single Layer Thickness Research Articles

Direct methane activation by atomically thin platinum nanolayers on two-dimensional metal carbides

Efficient and direct conversion of methane to value-added products has been a long-term challenge in shale gas applications. Here, we show that atomically thin nanolayers of Pt with a single or double atomic layer thickness, supported on a two-dimensional molybdenum titanium carbide (MXene), catalyse non-oxidative coupling of methane to ethane/ethylene (C2). Kinetic and theoretical studies, combined with in-situ spectroscopic and microscopic characterizations, demonstrate that Pt nanolayers anchored at the hexagonal close-packed sites of the MXene support can activate the first C–H bond of methane to form methyl radicals that favour desorption over further dehydrogenation and thus suppress coke deposition. At 750 °C and 7% methane conversion, the catalyst runs for 72 hours of continuous operation without deactivation and exhibits >98% selectivity towards C2 products, with a turnover frequency of 0.2–0.6 s−1. Our findings provide insights into the design of highly active and stable catalysts for methane activation and create a platform for developing atomically thin supported metal catalysts. The challenge in non-oxidative coupling of methane lies in the activation of the first C–H bond while avoiding further dehydrogenations, which lead to the formation of coke. Here, atomically thin platinum nanolayers on two-dimensional molybdenum titanium carbides are reported as a superior catalyst for this reaction owing to reduced coke formation.

Study on impact resistance of composite rocket launcher

Abstract The transient impact load during the launch of a rocket at sea threatens the safety of the launcher and the deck structure of the launch platform. In view of the impact resistance of the offshore rocket launcher system, this paper takes the real-scale rocket launcher system as the research object and establishes the analysis model of the fiber-reinforced composite rocket launcher based on the finite element method. Then, we explore the factors of the thickness by finite element simulation method and the angle and the position of IM7 fiber-reinforced composite, which influence the impact resistance property of the rocket launcher. The results show that the fiber-reinforced composite rocket launcher can effectively reduce the impact response of the structure and improve the impact resistance of the structure. The best laying scheme is to lay four layers of IM7 fiber material on both sides of the panels of the fixed bracket and the webs of the erector, respectively, with a single layer thickness of 0.75 mm and a laying angle of [90°/∓45°/90°].

Structural, interface texture and toughness of TiAlN/CN multilayer films

Microstructure evolution study of TiAlN/CN x multilayer films with similar single layer thickness (the thickness of individual TiAlN layer: L TiAlN , L TiAlN /L CN x = 1) in the range of 0.9 nm to 13.7 nm shows that the structure of the TiAlN/CN x -MFs changes with the change of L TiAlN . TiAlN/CN x -MFs with L TiAlN of 0.9 nm exhibit a nanocomposite structure with embedded nano-sized crystalline TiAlN particles in the matrix. Due to the template effect of the TiAlN layers when L TiAlN is 2.6 nm, the CN x layers will partially crystallize and grow coherently with the TiAlN layers. Analysis of the different relationships between the TiAlN/CN x interface reveals one type of orientation relationship between the fcc TiAlN and crystalline CN x layers: (111) TiAlN‖(111) C 3 N 4 . Interfaces of the TiAlN/CN x are sharp but with the expansion of the TiAIN lattice spacing and the shrinking of CN X relative to itself, the lattice spacing will vary near the interface region. Further increasing L TiAlN , the CN x layers will exhibit completely amorphous structures and slowly lose their coherent interfaces, triggering a rapid decline in hardness and toughness. Maximum hardness of the MFs is 27.2 GPa when the L TiAlN is 0.9 nm, while the fracture toughness of the MFs with L TiAlN of 2.6 nm is almost 1.5 times that of the other MFs. To obtain high hardness and enhanced toughness in MFs, crystallization of CN x layers and coherent growth are required. • TiAlN/CNx-MFs with LTiAlN of 0.9 nm exhibit nanocomposite structure • Extremely fine TiAlN crystals were formed • The atomic mixing or the bond energy lead to the change of lattice spacing • TiAlN nc grains are separated by a matrix phase

Fabrication and function examination of PZT-based MEMS accelerometers

In this study, a hybrid sol-gel method was used to fabricate Pb(Zr0.52Ti0.48)0.98Nb0.02O3 (PNZT) piezoelectric thick films. By preparing Pb(Zr0.52Ti0.48)0.98Nb0·02O3 sol-gel solutions and mixing them with PZT-5A piezoelectric powders, therefore, the thickness of single layer coating can be increased and reduce the risk of film cracks. The proposed PNZT films have the dielectric constant of 1750, dielectric loss of 0.063, remnant polarization of 58 μC/cm2, and d33 of 133 p.m./V. Piezoelectric cantilever beam MEMS accelerometers were then designed, simulated and fabricated via photolithography methods on Si substrates. The sensitivity and natural frequency of the cantilever beam accelerometer are 16.8 mV/g and 200Hz, respectively. Finally, a cantilever beam accelerometer is successfully applied for the server hard-drive fault detection.

Cyclic Test on a Full-Scale Unreinforced Masonry Building Repaired with Steel Fiber-Reinforced Mortar Coating

The present work reports the results of two quasi-static reverse cyclic tests performed on an unreinforced hollow clay block masonry building before and after repairing with a single 30-mm thick layer of mortar applied on the façades. Unlike traditional coating-based retrofitting techniques, the one proposed herein adopts a cement-based mortar reinforced with short high-strength steel fibers randomly diffused in the mortar matrix. In order to assess the effectiveness of the strengthening intervention, a preliminary cyclic test was carried out on the unstrengthened building in order to predamage masonry. The experimental results showed that the repaired structure exhibited a significant improvement of seismic behavior both at the serviceability and ultimate limit state conditions. Moreover, based on the observed ultimate ductility of the retrofitted building, some considerations on the behavior factor are reported.

Design and operation of a portable micro-photoluminescence spectrometer for education on semiconductor quantum structures and graphene sheets.

The design and operation of a portable micro-photoluminescence spectrometer for applications in education is described. Guidelines are a compact, robust, portable, and flexible design; operation without cryogenic media for sample cooling; and a limited budget. Targeted samples are semiconductor quantum structures emitting in a wavelength range of 600-1000nm and graphene sheets. The portable spectrometer includes a reflected-light microscope with a motorized sample stage of 156nm step size, a thermoelectric sample cooler allowing temperatures down to 196K, a green and a blue laser for focused excitation, a monochromator with 0.18nm spectral resolution, and a cooled camera as the image sensor. For demonstration of the capabilities of the spectrometer, measurements of the quantized energy levels of molecular beam epitaxy grown GaAs quantum dots (QDs) are shown. Here, different sample designs are used, the sample temperature as well as the laser excitation power and energy is varied, and the respective influence on the measurements is discussed. A clear QD shell structure with four states is shown for a sample, where approximately four QDs are directly excited by a focused laser. Limitations of the spectrometer for QD characterization mainly due to the waiver of cryogenic media for sample cooling are discussed. As a further example, which does not require sample cooling, local Raman spectroscopy of a graphene sheet is demonstrated where clear Raman signatures allow the identification of a single-layer thickness.

Graphene-Based Nanomaterials as the Cathode for Lithium-Sulfur Batteries.

The global energy crisis and environmental problems are becoming increasingly serious. It is now urgent to vigorously develop an efficient energy storage system. Lithium-sulfur batteries (LSBs) are considered to be one of the most promising candidates for next-generation energy storage systems due to their high energy density. Sulfur is abundant on Earth, low-cost, and environmentally friendly, which is consistent with the characteristics of new clean energy. Although LSBs possess numerous advantages, they still suffer from numerous problems such as the dissolution and diffusion of sulfur intermediate products during the discharge process, the expansion of the electrode volume, and so on, which severely limit their further development. Graphene is a two-dimensional crystal material with a single atomic layer thickness and honeycomb bonding structure formed by sp2 hybridization of carbon atoms. Since its discovery in 2004, graphene has attracted worldwide attention due to its excellent physical and chemical properties. Herein, this review summarizes the latest developments in graphene frameworks, heteroatom-modified graphene, and graphene composite frameworks in sulfur cathodes. Moreover, the challenges and future development of graphene-based sulfur cathodes are also discussed.

Two-dimensional talc as a van der Waals material for solid lubrication at the nanoscale

Talc is a van der Waals and naturally abundant mineral with the chemical formula Mg3Si4O10(OH)2. Two-dimensional (2D) talc could be an alternative to hBN as van der Waals dielectric in 2D heterostructures. Furthermore, due to its good mechanical and frictional properties, 2D talc could be integrated into various hybrid microelectromechanical systems, or used as a functional filler in polymers. However, properties of talcas one of the main representatives of the phyllosilicate (sheet silicates) group are almost completely unexplored when ultrathin crystalline films and monolayers are considered. We investigate 2D talc flakes down to single layer thickness and reveal their efficiency for solid lubrication at the nanoscale. We demonstrate by atomic force microscopy based methods and contact angle measurements that several nanometer thick talc flakes have all properties necessary for efficient lubrication: a low adhesion, hydrophobic nature, and a low friction coefficient of 0.10 ± 0.02. Compared to the silicon-dioxide substrate, 2D talc flakes reduce friction by more than a factor of five, adhesion by around 20%, and energy dissipation by around 7%. Considering our findings, together with the natural abundance of talc, we put forward that 2D talc can be a cost-effective solid lubricant in micro- and nano-mechanical devices.

Microwave Heat-Treated Electronic Waste Constituted X-Band Radar Absorbing Structure Using Electromagnetic Mixing Model Assisted Optimization Strategy

Potential radar absorbing material (RAM) for suppressing electromagnetic (EM) wave over a range of oblique angles of incidence are needed in many applications. In this article, an attempt is being made to build cost-effective and efficient RAM using the EM characterization of microwave heat-treated (MHT) electronic waste followed by an EM mixing model-assisted analytical approach. The robust and facile top-down fabrication technique is employed for the development of heterogeneous composites, which are further subjected to microwave heat treatment at distinct power wattages. The magneto-dielectric spectrographic analysis of samples is carried out in the range of 8.2 to 12.4 GHz. The Debye parameters are optimized and succeeded to obey EM property of the synthesized samples. Jaya's algorithm is adopted for the optimal design of single and dual-layer RAMs at normal and oblique angle incidence based on the constitutive EM parameters under certain restrictive conditions. The embraced MHT method prompts an improvement in microstructure coherency that further increases absorption bandwidth (BW). As a result, a 2.1 mm thick single layer RAM achieves a minimum reflection coefficient (RC) of -17.1 dB at 10.3 GHz with a 100% BW below -10 dB threshold. The groundbreaking findings are obtained by performing a three-fold study of dual-layer RAMs, culminating a minimum RC of -47.8 dB at 11.8 GHz with a layer thickness of 1.8 mm. This article shows that the microwave heat-treated composites have enormous potential in the development of lightweight and broadband RAMs for stealth applications.

Oil-gas-water system study in fine reservoir description researches—taking Yulou oil-bearing sets in the West depression in Liaohe Basin in China as an example

Taking a steam flooding experimental area in the West depression in Liaohe Basin in China as an example, the development characteristics of reservoir oil-gas-water system is studied using methods of geological statistics and comparative analysis based on the comprehensive of core, well logging, analytical test, and development performance data. The aimed stratum has good oil-bearing properties, and the oil content level of cores is mainly oil sand and oil-bearing sandstone. The lower limit of effective reservoir has a porosity of 28% and a permeability of 30 mD. In the aimed stratum, the oil viscosity increases gradually with the increase of oil density, and the correlation between the wax content and density of oil is not obvious. With the increase of oil viscosity, the resin and asphaltene contents increase. And with the increase of oil density, the resin and asphaltene contents gradually increase as well. The oil density is relatively big, and most of the 14 samples have a density greater than 0.97 g/cm3. The oil viscosity is mostly greater than 5000 mpa s. The wax content is relatively low (mostly less than 2.5%) with the maximum of 4%. The contents of resin and asphaltene are both greater than 38%, which are relatively high. The formation water is NaHCO3 type which is slightly alkaline. The oil-water contacts of different reservoirs in Yulou oil-bearing sets I are between depth of 1020 m and 1060 m. The distribution of oil layers is jointly controlled by the sediments and structures factors. For the thickness of single oil layer, the maximum is more than 5 m, while the minimum is only one to 2 m. The edge and bottom water plays a very important role in the development of oilfields. In designing and executing various EOR methods in the process of thermal recovery, the influence of reservoir oil-gas-water system should be fully taken into account.

The Development Characteristics and Distribution Predictions of the Paleogene Coal‐measure Source Rock in the Qiongdongnan Basin, Northern South China Sea

AbstractThere are known to be enormous Cenozoic coal‐type oil and gas resources located in the basins of the South China Sea, among which the Paleogene coal‐measure source rock are one of the main source rock. In order to more effectively analyze the distribution laws of coal‐measure source rock in marginal sea basins and guide coal‐type oil and gas explorations, the Oligocene coal‐measure source rock in the Qiongdongnan Basin were selected as examples in order to systematically analyze the types, development characteristics, control factors, and distribution prediction methods of coal‐measure source rock in marginal sea basins. The Qiongdongnan Basin is located in the northern region of the South China Sea. Previous explorations of the area have determined that the Oligocene coal‐measure source rock in the Qiongdongnan Basin have typical “binary structures”, which include coal seams and terrigenous marine mudstone. Among those, the terrigenous marine mudstone has been found to greatly expand the scope of the coal‐measure source rock. In addition, the coal seams which have been exposed by drilling have been observed to have the characteristics of thin single layer thickness, many layers, and poor stability. Meanwhile, the terrigenous marine mudstone has the characteristics of large thickness and wide distribution. The development of coal‐measure source rock is known to be controlled by many factors, such as paleoclimate and paleobotany condition, paleo‐structure and topography, paleo‐geography, rise and fall of base level, and so on. In accordance with the comprehensive analyses of various control factors of coal‐measure source rock, and the changes in water body energy in sedimentary environments, a genetic model of the “energy belt” for the development and distribution of coal‐measure source rock was proposed. Also, the development and distribution characteristics of coal‐measure source rock in different types of energy belts were clarified. Then, based on the development and distribution characteristics of coal‐measure source rock and their controlling factors, prediction methods of the distribution ranges of coal‐measure source rock were proposed from both qualitative and (semi‐) quantitative aspects. That is to say, a method for (semi‐) quantitative predictions of the distribution ranges of coal‐bearing intervals based on model wave impedance inversion and neural network wave impedance inversion, along with a method for (semi‐) quantitative predictions of the distribution ranges of terrigenous marine mudstone based on topographical slopes, were introduced in this study.

Study on the Preparation and Test of Hydrodynamic Focusing Microfluidic Chip Fabricated by Liquid Crystal Display Mask Photo-Curing Method

Microfluidic chips with the function of hydrodynamic focusing is widely used in the field of cell electroporation, droplet formation, drug screening and particle enrichment. Due to the small channel size of microfluidic chip, the existing processing methods have the defects of high fabrication cost or low dimensional consistency, the drawback is particularly prominent at small fabrication quantity. In this study, hydrodynamic focusing microfluidic chip was successfully fabricated by Liquid Crystal Display (LCD) mask photo-curing method with high efficiency and precision, the mechanism of curing parameters on the accuracy of microstructure was investigated, the hot pressing process was proposed to realize the bonding of cured photosensitive resin and glass substrate. By analyzing the focusing width of typical cross structure channel, a hydrodynamic focusing chip was designed. The effects of exposure time and single layer thickness on whole curing time was studied, the factors affecting the surface roughness were investigated, and the dimensional accuracy control method was proposed. The effect of bonding pressure on cured resin temperature was calculated and tested. The focusing width was verified by theoretical calculation and experiment. The mechanism for the inconsistency between the experimental focusing width and the theoretical focusing width was analyzed. The research proposed a solution of microfluidic design, fabrication, bonding and testing, which could provide a theoretical and methodological support for the efficient fabrication of microfluidic chips.

Application of seismic sedimentology to the western slope of northern Songliao basin

During the sedimentary period of Saertu reservoir on the western slope of the northern Songliao basin, delta front and shore-shallow lake subfacies are mainly developed, which have the characteristics of few sandstone layers and thin single layer thickness. The lithology of thin layer or thin interlayer can not be distinguished clearly by seismic response on conventional seismic section, and it is difficult to identify them. Geophysical response characteristics of channel sand bodies are defined by well-seismic combination. Under the guidance of seismic sedimentology, the qualitative and quantitative prediction of channel sand bodies is carried out by using 90°-phase conversion, stratal slicing and waveform indication inversion techniques. The results show that the seismic reflection axis is symmetrical with respect to the top and bottom surface of sandstone, and the channel sand body has obvious characteristics and completely corresponds to wave peak reflection. The channel bodies of S1 and S23 reservoir formation are separated respectively into two stages by using the amplitude attributes of stratal slices, and the coincidence rate of reservoir prediction to wells is 78%~84%, with an average of 79.7%. The waveform indicator inversion technique is used to predict the channel sand body thickness of the four stages, and the error of sand body thickness to well is 0~1.6m, with an average of 0.32m.

Application analysis of shale gas core hyperspectral in weican-1 well

Hylogger core scanning system is used to detailed scan shale gas drilling cores, obtaining visible-near infrared (spectral range 380nm-1100nm),short-wave infrared (spectral range 1100nm-2500nm) spectral curves and high-definition core images. Taking Well weican 1 in the West Taikang Uplift in the South China North Basin as an example, based on the analysis of clay mineral types in the core of the target layer, it is judged to be an alkaline deposit environment rich in iron and magnesium with a temperature of about130°C. Combined with mineral information and core image, the core of the target layer is divided,mud shale is developed, the cumulative thickness exceeds 400m, the maximum single layer thickness reaches 38m, at the same time, the hydrocarbon absorption characteristics of the shale section are obvious, it shows a good prospect for shale gas in the region.

Superior Capsule Reconstruction Using Fascia Lata Allograft Compared With Double- and Single-Layer Dermal Allograft: A Biomechanical Study

To biomechanically characterize superior capsule reconstruction (SCR) using fascia lata allograft, double-layer dermal allograft, and single-layer dermal allograft for a clinically relevant massive irreparable rotator cuff tear involving the entire supraspinatus and 50% of the infraspinatus tendons. Eight cadaveric specimens were tested in 0°, 30°, and 60° abduction for (1) intact, (2) massive rotator cuff tear, (3) SCR using fascia lata, (4) SCR using double-layer dermis, and (5) SCR using single-layer dermis. Superior translation and subacromial contact pressure were measured. Statistical analysis was conducted using repeated measures ANOVA or paired t test with P < .05. Massive rotator cuff tear significantly increased superior translation of the humeral head at all abduction angles (P < .05). At 0° abduction, all SCR conditions significantly decreased superior translation compared with the massive tear but did not restore translation (P < .05) to intact. Fascia lata and double-layer dermis SCR restored superior translation to intact at 30° and 60° of abduction, but single-layer dermis did not. Subacromial contact pressure at 0° of abduction significantly decreased with SCR with fascia lata and double-layer dermis compared with tear. At 30°, all SCR conditions significantly decreased subacromial contact pressure. Single-layer dermis graft thickness significantly decreased more than fascia lata during testing (P= .02). For SCR tensioned at 20° glenohumeral abduction, all 3 graft types may restore superior translation and subacromial contact pressure depending on the glenohumeral abduction angle; fascia lata and double-layer dermis may be more effective than single-layer dermis. If a dermal graft is to be used for SCR, consideration should be given to doubling the graft for increased thickness and better restorative biomechanical properties, which may improve clinical outcomes following SCR.

Nanoscale liquid hydrocarbon adsorption on clay minerals: A molecular dynamics simulation of shale oils

As adsorption can influence the phase behavior of shale oils, and consequently their transport, understanding the adsorption behavior of liquid hydrocarbons in shale is essential for the utilization of this valuable resource. In this work, the adsorption of n-nonadecane (saturated hydrocarbon), toluene and 3-methylphenanthrene (aromatic hydrocarbons), and porphyrin (resin) in the slits of clay minerals (montmorillonite, kaolinite, and illite with 10 nm slit apertures) at 358 K and 30 MPa was evaluated through molecular dynamics simulations. The single adsorption layer thicknesses of different hydrocarbons adsorbed on montmorillonite were 0.31–0.48 nm. The total thickness and volume proportion of the adsorption layers, which can be used as a measure of adsorption capacity, were 0.96–1.57 nm and 12.0–23.5%, respectively, and varied with the hydrocarbon component in the order of resin > aromatic > saturated hydrocarbon. The hydrocarbon adsorption capacity of montmorillonite is stronger than that of illite and kaolinite. The structural morphology of hydrocarbon molecules, in addition to the adsorbent pore size, strongly affects adsorption behavior. The adsorption of the long-chain alkane n-nonadecane occurred with minimal distinction between layers. This previously predicted disorder was seen to increase with distance from the mineral surface. The adsorption capacity increased with the polarity of the hydrocarbon component owing to the induction of van der Waals forces, which are reduced along with the Coulomb force at greater distances between the hydrocarbon and clay minerals. Adsorptive affinities are important for crude oil flow rates. Shale oil contains more high-adsorptive oil fractions, making it less fluid and difficult for production. Although this study profiles the nanoscale adsorption behavior of hydrocarbons, it can also function as a meaningful reference for the assessment of shale oil fluidity.

Application of the decision tree method to lithology identification of volcanic rocks-taking the Mesozoic in the Laizhouwan Sag as an example

The decision tree method can be used to identify complex volcanic rock lithology by dividing lithology sample data layer by layer and establishing a tree structure classification model. Mesozoic volcanic strata are widely developed in the Bohai Bay Basin, the rock types are complex and diverse, and the logging response is irregular. Taking the D oilfield of the Laizhouwan Sag in the Bohai Bay Basin as an example, this study selects volcanic rocks with good development scales and single-layer thicknesses of more than 0.2 m as samples. Based on a comparison of various lithology identification methods and both coring and logging data, using the decision tree analysis method and the probability density characteristics of logging parameters, six logging parameters with good sensitivity to the response of the volcanic rocks of the above formation are selected (resistivity (RD), spontaneous potential (SP), density (ZDEN), natural gamma ray (GR), acoustic (DT), and compensated neutron correction (CNCF) curves), which are combined to form a lithology classifier with a tree structure similar to a flow chart. This method can clearly express the process and result of identifying volcanic rock lithology with each logging curve. Additionally, crossplots and imaging logging are used to identify the volcanic rock structure, and the core data are used to correct the identified lithology. A combination of conventional logging, imaging logging and the decision tree method is proposed to identify volcanic rock lithology, which substantially improves the accuracy of rock identification.

Mathematical modelling of transport of single and double charged ions through layered ion exchange membranes

Monovalent selectivity of ion exchange membranes is important for such areas as hardness removal, stabilization of mining waters and fining of foods. The modern approach to the creation of monovalent selective ion exchange membranes is layer-by-layer adsorption of polyelectrolytes onto a membrane surface, which showed significant improvement in comparison with previously used approaches, most notably in comparison with the creation of a single thick layer of polyelectrolyte. Despite the practical importance, the mechanism of improvement in selectivity is unknown. Knowledge of the distribution of ions within the membrane and adjacent layers of solution would answer the question of the mechanism, but such information is unobtainable through the experiment. Hence we develop the 1D mathematical model based on Nernst-Planck-Poisson equations to describe the fluxes and the concentrations of single and double charged ions, as well as potential drop / current density through the ion exchange membrane. In this paper we formulate the problem and list experimentally determined parameters. Results of calculations will be compared with experimentally recorded I-V and V-t curves.

The Bearing Capacity Evaluations of a Spread Footing on Single Thick Stratum or Two-Layered Cohesive Soils

Nowadays many countries plan to increase the percentages of renewable energies by developing offshore wind power. Due to the large sizes of offshore foundations, such as spudcan footings of jack-up barges or pile anchors of wind turbines, the affected soil depth range caused by the foundation under loading can be relatively deep, so the affected range may include a single thick layer or stratified soils. This paper utilizes limit analysis and FLAC numerical simulation to investigate the bearing capacity of a footing on single thick stratum or two-layered cohesive soils. Under nature deposition condition, the undrained shear strength of most cohesive soil approximately increases linearly as the depth increases. The closed-form upper bound solutions of fully rough or fully smooth footings on thick cohesive soils are provided, for the purpose of fast evaluations in practical engineering, and the outcomes are within the results from the FLAC simulation and slip circle method. The problems of punch-through shear failure or soil squeezing could be critical for two-layered soils under some conditions, and the associated bearing factors and the failure mechanisms from different methods are demonstrated and discussed in the article.

Experimental study on mechanical behavior of double-layer toughened sandwich glass with two-side simple support

To study the mechanical behavior of double-layer toughened sandwich glass with two-side simple support under out-of-plane bending, a total of sixty-four specimens with different test parameters were experimentally investigated in this paper. The main parameters of specimens include thickness of single layer, supporting width, and loading length. It was demonstrated that the specimens failed with all pieces of cracks combined together as an entire unit rather than to separate into a large number of glass fragments. What's more, the cracks appeared only in the lower layer of the toughened sandwich glass, extending in a way similar to the spider web. The ultimate bending strength and bending stiffness of the toughened sandwich glass are enhanced with the increase of the thickness of single layer, the supporting width, and the loading length. Among the above parameters, the thickness of single layer plays a leading role in enhancing the ultimate bending strength and bending stiffness of the toughened sandwich glass. Nevertheless, the supporting width only has a slight effect on improving the ultimate bending strength and bending stiffness. Based on the bending theory of thin plates, the simplified design formulas were presented to evaluate the ultimate bending strength of double-layer toughened sandwich glass with two-side simple support under out-of-plane bending, which was verified to be reasonable and accurate.