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One of the highly attractive research directions in the electrochemiluminescence (ECL) field is how to regulate and improve ECL efficiency. Quantum dots (QDs) are highly promising ECL materials due to their adjustable luminescence size and strong luminous efficiency. MoS2NSs@QDs, an ECL emitter, is synthesized via hydrothermal methods, and its ECL mechanism is investigated using cyclic voltammetry and ECL-potential curves. Then, a stable and vertical attachment of a triplex DNA (tsDNA) probe to the MoS2nanosheets (NSs) is applied to the electrode. Next, an innovative ECL sensor is courageously empoldered for precise and ultrasensitive detection of target miRNA-199a through the agency of ECL-resonance energy transfer (RET) strategy and a dextrous target-initiated catalytic three-arm DNA junction assembly (CTDJA) based on a toehold strand displacement reaction (TSDR) signal amplification approach. Impressively, the ingenious system not only precisely regulates the distance between energy donor–acceptor pairs leave energy less loss and more ECL-RET efficiency, but also simplifies the operational procedure and verifies the feasibility of this self-assembly process without human intervention. This study can expand MoS2NSs@QDs utilization in ECL biosensing applications, and the proposed nucleic acid amplification strategy can become a miracle cure for ultrasensitive detecting diverse biomarkers, which helps researchers to better study the tumor mechanism, thereby unambiguously increasing cancer cure rates and reducing the risk of recurrence.

Handing stability and ride comfort, basic indexes to evaluate vehicle performance, usually cannot be guaranteed simultaneously. Given the contradiction between the two indexes, a new type of suspension – balanced suspension, has attracted wide attentions for years. Balanced suspensions are a device that converts the movement of a wheel into force at the other wheels through a mechanical or hydraulic structure, which might improve ride comfort/handling stability while maintaining the handling stability/ride comfort. As the hydraulically interconnected suspension and hydro-pneumatic suspension show disadvantages of high cost and high installation space requirement, a specific balanced suspension which is connected through a mechanical structure is presented and thoroughly analyzed in this paper. The balanced suspension connects the front and rear suspension motion of the vehicle by means of the lever mechanical connection structure to obtain the comprehensive performance of enhanced vehicle’s ride comfort and handling stability. The half-vehicle mathematical model for ride comfort and the multi-body dynamics model for handling stability are established for the comparison and analysis of the dynamic performance of vehicle when the balanced suspension on and off. In addition, experimental tests of the modified vehicle prototypes when the balanced suspension on and off on the ride comfort and handling stability are conducted. Similar with the simulation results, experimental tests show that the handling stability is nearly unchanged while the ride comfort improves about 15.9% when the balanced suspension is on.

Brake-by-wire systems are one of the key components in intelligent/unmanned vehicles that have attracted worldwide attention. Testing and evaluation of brake-by-wire systems are a significant step during the development of the technology of vehicular braking and further the advancement of intelligent/unmanned vehicles. Using the test bench to simulate different road adhesion coefficients (i.e. road surfaces) and to complete the testing and evaluation of the vehicle braking systems is of great significance and importance. A test bench for simulation of vehicular braking of 1/4 vehicle is presented and investigated in this article. It is composed of a motor, two rollers, a 1/4 vehicle suspension system, a magnetic powder clutch, a flywheel, sensors, a signal acquisition and processing system, and a controller. The wheel and vehicle speeds are simulated by the rollers and flywheel speeds, respectively. The translational kinetic energy of 1/4 vehicle is simulated by the rotational kinetic energy of the flywheel. The signal acquisition and processing system is used to acquire and process the experimental signals, such as rotational speeds and torques during tests. The magnetic powder clutch with adjusted applied currents in the test bench is used to real-timely simulate roads with different adhesion coefficients. Based on the working principle of the test bench and the fundamentals of vehicle dynamics, the prototype of the test bench is established and the simulation approach of the translational kinetic energy of 1/4 vehicle is investigated. The mathematical model of the real-time simulation about roads with different adhesion coefficients based on the magnetic powder clutch with real-time controllable transmitted torque is established. With the built 1/4 vehicle braking systems based on the test bench and road, and the corresponding established models, the comparison and analysis of the simulation results of various road surfaces are conducted. Experiments are sequentially implemented to verify the feasibility and effectiveness of the test bench.

Abstract: Near-infrared (NIR) diffuse reflectance spectroscopy has become an attractive technique for quality assurance of fruits, drugs, vegetables, and foods. In this work, the information on chemical composition of Siraitia grosvenoriiwas acquired by NIR, and then a calibration model for the prediction of total sugar content (TSC) was developed using chemometric techniques. One hundred and fifty samples were used as calibration set to develop model, while 40 unknown samples were used for prediction, using phenol-concentrated sulphuric acid assay as reference value. Several spectra preprocessing methods and wavelength selection techniques combined with partial least squares regression were compared, and then standard normal variate coupled with Savitzky–Golay derivative was selected for spectra processing and competitive adaptive reweighted sampling method was applied to extract the informative wavelengths related to the prediction of TSC. The performance of the obtained model has been evaluated by external validation, the square of correlation coefficient (R2) are 0.9097 for a separate blind set consists of 40 unknown samples. Additionally, the result of paired ttest (p?=?0.3608) illustrated that there is no significant differences between NIR and wet chemistry analysis. These results demonstrated that NIR spectroscopy has the potential to be a time saving and cost-effective method for the determination of the TSC in S. grosvenorii. Graphic abstract:

To monitor illegal addition of tadalafil and its analogues in health food, a new polyclonal antibody was prepared by immunizing New Zealand white rabbits with a common skeleton structure hapten combined with an unsaturated linear alkyl arm hapten strategy, which could simultaneously recognize tadalafil, amino tadalafil and N-Desmethyl tadalafil. A microwell lateral flow immune- chromatographic assay (mwLFIA) method combined with simple sample pretreatment was developed. The mwLFIA showed that the LOD for three tadalafil drugs was between 0.05 ng mL−1and 0.30 ng mL−1, the cut-off values were between 50 ng mL−1and 100 ng mL−1. Cross-reactivity (CR) results showed no interference from substances with similar structures, indicating a good specificity against tadalafil, amino tadalafil and N-Desmethyl tadalafil. The average recoveries of three drugs in spiked health wine and oral liquid ranged from 78.7% to 117.8% with an RSD of less than 15%, showing a good aggreement with the results of HPLC-MS/MS method. The developed mwLFIA strip was suitable for the rapid detection of tadalafil and its analogues in health wine and oral liquid samples.

We investigate the polarization effect in intersubband transitions in polar and nonpolar GaN-based multiple-quantum well (MQW) structures for terahertz (THz) emissions by using systematic comparisons and design a nonpolar GaN/Al0.2Ga0.8N two-well-based MQW structure with an emitting photon of 7.27 THz (30.07 meV). Its lower energy separation (92.7 meV) matches the resonant phonon depopulation condition for better population inversion. It shows a lower threshold current density Jthat all temperatures (1.548 kA/cm2at 90 K) and a higher output power of up to 86.1 mW at 5.8 K and 33.6 mW at 100 K. Our results for the polar GaN MQW are very close to the experimental data in the literature. We find that the Jthof the nonpolar GaN MQW increases more slowly than that of the polar GaN MQW as temperature increases, indicating the nonpolar GaN MQW may be a worth-trying direction for improving the operation temperature. These results can provide meaningful references for the design and fabrication of nonpolar GaN-based THz MQW or quantum cascade structures.

Liver metabolism is commonly considered the major determinant in drug discovery and development. Many in vitrodrug metabolic studies have been developed and applied to understand biotransformation. However, these methods have disadvantages, resulting in inconsistencies between in vivoand in vitroexperiments. A major factor is that they are static systems that do not consider the transport process in the liver. Here we developed an in vitrodynamic metabolic system (Bio-PK metabolic system) to mimic the human pharmacokinetics of tolbutamide. Human liver microsomes (HLMs) encapsulated in a F127'-Acr-Bis hydrogel (FAB hydrogel) were placed in the incubation system. A microdialysis sampling technique was used to monitor the metabolic behavior of tolbutamide in hydrogels. The measured results in the system were used to fit the in vitrointrinsic clearance of tolbutamide with a mathematical model. Then, a PBPK model that integrated the corresponding in vitrointrinsic clearance was developed to verify the system. Compared to the traditional incubation method, reasonable PK profiles and the in vivoclearance of tolbutamide could be predicted by integrating the intrinsic clearance of tolbutamide obtained from the Bio-PK metabolic system into the PBPK model. The predicted maximum concentration (Cmax), area under the concentration-time curve (AUC), time to reach the maximum plasma concentration (Tmax) and in vivoclearance were consistent with the clinically observed data. This novel in vitrodynamic metabolic system can compensate for some limitations of traditional incubation methods; it may provide a new method for screening compounds and predicting pharmacokinetics in the early stages, supporting the development of compounds.

The pyrolysis of asphaltenes under hydrothermal environments covering the subcritical and supercritical regions of water was applied, and the influence of the presence of H-donors was surveyed by a reaction kinetics analysis based on the lumping approach. Under hydrothermal environments, the pyrolysis of asphaltenes consisting mainly of condensation to coke and decomposition to maltenes is significantly faster than that under a N2environment. The H-donors introduced, decalin or maltenes, may provide nonaromatic H atoms, capping the carbon radicals essential to pyrolysis. Accordingly, the apparent activation energies of the condensation and the decomposition of asphaltenes both increase to varying degrees. The pyrolysis of asphaltenes in the presence of a small quantity of decalin is seriously retarded in subcritical water but recovers rapidly in supercritical water owning to the promoted initiation efficiency at high temperature. Accompanied by a large amount of maltenes, the decomposition to maltenes involved in the original pyrolysis network of asphaltenes can be neglected.

Magnetic solid phase extraction based on a 3D reduced graphene oxide composite coupled with spectrofluorometry was proposed to determine the presence of trace rhodamine B in chili powder and tap water. The characterization results showed that Fe3O4covered the surface of the 3D reduced graphene oxide (3D-RGO) composite. The adsorption behaviour and adsorption capacity of the 3D-RGO composite were investigated. Several significant factors that affect the adsorption and desorption performance were optimized. The proposed method gave a wide linear range, from 0.025 to 150 μg L−1with R2= 0.9991, and low limits of detection (3Sb) and quantification (10Sb) of 0.0074 μg L−1and 0.025 μg L−1(n= 3), respectively. Furthermore, this method was successfully applied to determine the amount of rhodamine B in real samples, and the recoveries at three different spiked levels (0.03, 10, and 20 μg L−1) were in the range of 95.66–99.98%, with a relative standard deviation of less than 2.01% (n= 3).

In this investigation, micro crystalline diamond (MCD) and nanocrystalline diamond (NCD) films are deposited on cemented carbide (WC-Co) balls by hot filament chemical vapor deposition (HFCVD) technique. After deposition, MCD and NCD films are characterized by field emission scanning electron microscopy (FESEM) and Raman spectroscopy. Then frictional tests are carried out between CVD diamond coated balls and graphite. The results show that the MCD-graphite and NCD-graphite tribo-pairs exhibit comparable frictional coefficients, while the wear rate of graphite in MCD-graphite working pair is much higher than that of graphite in NCD-graphite working pair. Furthermore, the element oxygen is detected in the wear groove of graphite, suggesting the oxycarbide of working materials at the increased temperature due to the heat generated from the mechanical friction.

This Paper has analyzed the relationship between the generation of multiple piezoelectric effects and boundary conditions of piezoelectrics and the experiments have studied tertiary piezoelectric effect of piezoelectric quartz which is applied extensively in engineering practice. We processed our experiment by piezoelectric quartz crystal unit made by two pieces of X-cut piezoelectric quartz, parallel connected it to a capacitor with the equivalent capacitance of about 1,000 times of that of piezoelectric quartz crystal unit and then got the result of pure primary piezoelectric effect excluding tertiary induced effect; then compared it with conventional primary piezoelectric effect and concluded that tertiary piezoelectric effect of piezoelectric quartz is about 1.7% of primary piezoelectric effect; thus quantified longitudinally tertiary piezoelectric effect of piezoelectric quartz crystal, concluded that piezoelectric coefficient of tertiary effect of X-cut piezoelectric quartz is about 0.04 pC/N by experiment and got relative uncertainty and standard uncertainty of the results by such experiment methods respectively as 9.49×10-3 and 1.37×10-2. This study on tertiary piezoelectric effect has provided a new approach for improving precision and sensitivity of piezoelectric sensors.

To achieve airworthiness requirements, 90 second certification test is performed to show compliance. Recent development in the application of computer simulation makes it possible to improve aviation safety through aircraft evacuation simulation. The approach can replace the full scale certification demonstration and has attracted extensive interest. Various evacuation models have been developed to simulate evacuation process. This review investigates the modeling theoretical foundation and summaries individual applications in different scenarios. Moreover, a meaningful research field is proposed for further study.

A method of hole-drilling to estimate residual stress of welding joint of 2219-T87 aluminum alloy is proposed based on numerical simulation and measurement test. The influence of drilling-hole diameter to welding residual stress is first analyzed by numerical simulation, and the optimal diameter is obtained as 4.0 mm. In accordance with the diameter, carry out a test on measuring welding residual stress. And the maximum residual stress is calculated as 123.2 MPa.

Lane changing is the common behavior when cars are running. It will produce traffic conflict, reduce the efficiency of road system, and lead to malignant traffic accidents. Based on the analysis and evaluation of circular, cosine type, constant lane migration type and ladder lane transformation type, considering the driver behavior, vehicles control and dynamic constraints and thinking the obstacles as an infinite number of circles to idealize them, this paper establishes polynomial in horizontal and vertical directions respectively to indicate the position of vehicle, obtains the lane changing trajectory by testing whether the distance between circles meet some conditions, builds polynomial for the safe lane changing trajectory and real-time dynamic optimal distances between vehicles, and then utilize the MATLAB as the simulation tool to make experiments in various cases. Simulations and experimental results show that the method given in this paper to calculate the vehicle safety lane changing trajectory in the case of high-speed vehicle is feasible, effective and can give quickly safety lane changing distance.

protein was extracted from Antarctic krill (AK), then blended with sodium alginate (SA) , prepare the spinning solution, the rheological properties of spinning solution were studied by Brookfield DV-C digital viscosimeter. AKP/SA fibers were prepared via wet spinning with CaCl2 and PEG as coagulator .The morphology, tensile strength and thermal property of AKP/SA fibers were characterized by polarized light microscopy, monofilament strength tester and thermal gravimetric analysis (TGA) instrument. The result shows that the shear viscosities of spinning solution decrease with the increasing of shear rate and decreasing of concentration. the optimal Preparation Process of AKP/SA fibers were 5% concentration of SA, proportion of 1: 9 for AKP solution to SA solution, and proportion of 5:1 for CaCl2 to PEG. The cross-section of AKP/SA fiber is a jagged shape. Thermal property of AKP/SA fibers is similar to SA fibers.

For analyzing the effects of specimen-dimension on dynamic behaviors of fiber-reinforced composites, 4 kinds of CFRP specimens for different dimension were designed and made. The compressive loading tests were conducted by Ф 37mm split Hopkinson pressure bar (SHPB) system. The results show that the dynamic compression effects of specimen-dimension were exposed. An amount of Fiber-reinforced units inside the compressed area of the fiber-reinforced composites, then the experimental data are veracious for the material.

the best reception technologyis an important part of communication technology ,this article starting fromthe perspective of improving receivers,mainly analyzes how to make the maximumprobability of correct signals,and minimize the probability of error signalunder the same channel noise conditions,which means the best reception.And give thebinary knowing signal in the white noise of the channel under the condition ofthe best receive structure and principle,filter to accept, analysis ofcommunication technology theoretical research and practical application is verysignificant.

Stress of pressurizer surge line due to stratification is calculated with the help of finite analysis software, using both simplified temperature distribution and the temperature fields of CFD simulation result. Stress and displacement of pressurizer surge line are achieved. Evaluation of the fatigue life reduction due to stratification is done by using modified fatigue design curve and referring to environmental fatigue factor. The conclusions here indicate that it can’t be neglected that stratification reduces the fatigue life of pressurizer surge line.

In an effort to systematically review past research results, we conducted relative analysis examining the strength of the link between different social capital dimensions and organizational performance as well as potential moderators affecting this relationship. Analyses of past studies, we also found that this relationship depends on the social capital dimension considered, the institutional and industry contexts in which the organization operates. In this paper, we analysis the direct effect of social capital on organizational performance and deem that a main effect analysis providing an incomplete picture of performance implications of social capital. Internal resources and external environments are important to the development of a firm. Over all, our research contributes to a better understanding of social capital and organizational performance to explain variance in organizational performance.

American universities information security management system mostly established a special and independent information security management. Management system establishes the most CI0 management system, perfects the organizational structure and management content, which emphasis on differences, but the content covering were roughly the same. Enlightenment is as follows: first, we must establish independent information security management department. Second, we must be standardized, information security management content; Third, we must be installed with the professional information security work team.

ABSTRACTIt is unclear whether a mother who is negative for hepatitis B virus surface antigen (HBsAg) but positive for hepatitis B virus (HBV) is at potential risk for mother-to-child transmission of HBV. This study, using a paired mother-teenager population, aimed to assess whether maternal HBsAg-negative HBV infection (hnHBI) is a significant source of child HBV infection (HBI). A follow-up study with blood collection has been conducted on the 93 mother-teenager pairs from the initial 135 pregnant woman-newborn pairs 13 years after neonatal HBV vaccination. Serological and viral markers of HBV have been tested, and phylogenetic analysis of HBV isolates has been done. The HBI prevalence was 1.9% (1 hnHBI/53) for teenage children of non-HBI mothers, compared with 16.7% (1 hnHBI/6) for those of hnHBI mothers and 2.9% (1 HBsAg-positive HBV infection [hpHBI]/34) for those of hpHBI mothers. Similar viral sequences have been found in one pair of whom both the mother and teenager have had hnHBI. In comparison with the hpHBI cases, those with hnHBI had a lower level of HBV load and a higher proportion of genotype-C strains, which were accompanied by differentiated mutations (Q129R, K141E, and Y161N) of the “a” determinant of the HBV surface gene. Our findings suggest that mother-to-teenager transmission of hnHBI can occur among those in the neonatal HBV vaccination program.

Intelligent Transportation System (ITS) is a new industry and development greatly in recent years. The advanced electro-communication and computer technology combines detection, control, active warning and other information means. It provides a great guarantee for improving traffic safety and high efficiency. This paper puts forward the traffic rate-limiting sign and Lane Mark recognition method. In this study, four steps are applied to recognize a traffic and Lane Mark sign in an image. The first step, we transform the color space of image from RGB into HIS. Then the image blended HIS and RGB information is segmented. The third step, the text restrain and eliminate the isolated noise point based on eight-neighborhood. Finally, the traffic speed-limit sign and Lane Mark is recognized with template match. Our experiment results, in the out door, show that the method mentioned in the paper is useful and effective.

In this work, Chromium (Cr(III)) conversion coatings on Al 6063 alloy was prepared using trivalent-chrome compound (KCr(SO4)2) and H3PO4. The influence of five variables (i.e. deposition temperature, time, bath pH, and concentrations of (Cr(III)) compound (KCr(SO4)2) and H3PO4) on the preparation of (Cr(III)) coating on Al 6063 alloy was investigated using polarization curve in 3.5 wt% NaCl solution. The parameters of polarization curves were obtained from the extrapolation of anodic and cathodic Tafel lines. The optimum chemical passivation parameters of the chromium (Cr((III)) conversion coatings on the 6063 Al surface were obtained in this paper The results show the chromium (Cr(III)) conversion coatings formed under the optimal range present better corrosion resistance than those under the other conditions. Proper mechanisms were proposed to explain the above electrochemical behavior for the five treated conditions.

This article study the connecting performance of the corrosion high-strength bolts. According to the experiment of anti-slippery,the essay investigate anti-slippery coefficient, sliding load and ultimate load affected by the the extent of corrosion.The articl aslo study about the load-displacement cure of high-strength bolts connecting,which study The difference of the relation between load and displacement in each stages,cause by the whether the high-strength is corrosion.

In order to evaluate the dynamic behavior of the buffer of the Seagull 300 aircraft’s main landing gear, a drop model is built to simulate the drop dynamics using the software of LMS Virtual Lab Motion. The fluid damping force of the buffer, the air spring force of the buffer, the tire force of the landing gear and the weight of the fuselage are considered in the model. The simulation results are compared with the results of the Seagull 300 landing gears drop test, which proves the accuracy of the simulation model. Then the buffer performance and its influence factors are computationally discussed. This method gives a new way to study and improve the performance of the buffer system of an aircraft.

We report for the first time a cleavage phenomenon in the resonant peak of a piezoelectric quartz crystal (PQC) in liquid phase. In the presence of a strong longitudinal wave effect, an additional resonant peak appears in the conductance–frequency curve. With gradually increasing liquid density, the additional peak moves from low to high frequency region then disappears. The frequency of the additional resonant peak is sensitive to the change in liquid density. The frequency shift of the additional peak is linear with the liquid density in a given range. For a 5MHz PQC with a reflection distance of 16mm for longitudinal wave, the sensitivity to liquid density is 2.61×106Hzg−1cm3. The overlap between the primary resonant peak and the additional resonant peak causes a decrease in the intensity of the former and an increase in the intensity of the latter. In a combined impedance analysis method, the changes in surface mass loading, density and viscosity of the liquid were monitored simultaneously by a PQC sensor.

Through employing an external mirror that is tilted by an angle β=λ/2d in the external cavity, whose round-trip cavity length is one-half a Talbot distance, a laser diode array (LDA) is made to oscillate with only an in-phase supermode. This makes the far-field distribution of the LDA have a central-single-lobe far-field pattern, and it also makes the output from the LDA be nearly diffraction limited. However, if the phase-locked output energy from the LDA is extremely high, then the thermal radiation from the output deforms the external mirror stochastically. This makes the tilt angle (β) mismatched to the in-phase supermode, which results in undesirable supermode oscillations; so the far-field distribution of the LDA is no longer a central-single-lobe far-field pattern. Naturally, the intensity of the output from the LDA is attenuated, and the divergence loss is worsened. Therefore, suitable measures must be taken to guarantee the quality of the phase-locked output from the LDA. Accordingly, after analysis of the deformation of the external mirror, a novel one-spot and multispot processing (OMP) technology is developed. With special sensors, deformation of the external mirror is ascertained as a function of time. Then the deformation is compensated by appropriate equipment, which counteracts any bad influence on the angle β. The experiment significantly demonstrates that only the in-phase supermode oscillated in an extremely high-energy LDA after the implementation of OMP, allowing such lasers to satisfy the requirements of high-quality laser applications.

Abstract A novel fluorescein–porphyrinatozinc(II) hybrid, Zn(Fl–PPTPP), was synthesized and characterized by u.v.–vis., i.r., 1H-n.m.r, ESMS and elemental analyses. The supramolecular self-assembly of Zn(Fl–PPTPP) with an imidazolyl-linked porphyrinatomanganese(III), Mn(III)(p-ImBPTPP)Cl, complex has been studied by fluorescence spectroscopic titration, VPO measurements and ESMS, which indicates that the formation of the Zn(Fl–PPTPP)–Mn(III)(p-ImBPTPP)Cl. supramolecular complex is driven by coordinative bonding formed by the coordination of imidazolyl group in Mn(III)(p-ImBPTPP)Cl to Zn(II) in Zn(Fl–PPTPP). The association constant of the supramolecular complex was calculated from the fluorescence spectroscopic titration data. It was found that the conformation of the Zn(Fl–PPTPP)–Mn(III)(p-ImBPTPP)Cl supramolecular complex, the steric hindrance and the electronic effect of the fluorescein group linked to porphyrin through a flexible long alkoxy chain are all acting on the association constant of the Zn(Fl–PPTPP)–Mn(III)(p-ImBPTPP)Cl supramolecular complex. It seems that the steric hindrance and the electronic effect of the fluorescein group are the primary factors effecting the association constant of Zn(Fl–PPTPP)–Mn(III)(p-ImBPTPP)Cl supramolecular complex, especially the electronic effect of the fluorescein group, which is the reason for the association constant of Zn(Fl–PPTPP)–Mn(III)(p-ImBPTPP)Cl being smaller than that of ZnTPP–Mn(III)(p-ImBPTPP)Cl.

A series of zeolite X/activated carbon (AC) composites were prepared from the same starting materials at various activation time. The corresponding modified samples were obtained by being treated with diluted NH4Cl solution. The relationship between porosity development, surface properties, and CH4/N2 adsorption performance was investigated. The increase of micropore volume is beneficial to the improvement of CH4 and N2 adsorption capacity, but more sensitive for CH4. In addition, the polar functional groups of zeolite X/AC composites may enhance CH4 adsorption capacity. More importantly, both developing micropore structure and surface modification contributed to enhance the adsorption selectivity αCH4/N2. As the optimum sample of these studies, HZAC(24) showed CH4 adsorption capacity of 17.3 cm3/g and the highest adsorption selectivity αCH4/N2 of 3.4. The CH4 and N2 adsorption isotherms of all samples can be well fitted by the Langmuir–Freundlich model. HZAC(24) showed an excellent cyclability of adsorption/desorption of CH4 with a neglectable capacity loss after subsequent cycles. Moreover, HZAC(24) displayed relatively rapid adsorption kinetics. These properties of zeolite X/AC composites are essential for the adsorptive separation of CH4 from N2 in the pressure swing adsorption (PSA) process.