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Compared with single MOFs, MOFs@aerogels have ultra-high specific surface area, high porosity, good polymer compatibility and excellent structural pores, which can efficiently adsorb and remove pollutants in water. This paper introduced the structure and physicochemical properties of MOFs@aerogels, as well as the commonly used synthesis strategies of MOFs@aerogels. The advantages and disadvantages of the synthesis strategies and the challenges were analyzed. The adsorption conditions and adsorption properties of MOFs@aerogels for heavy metal ions and organic compounds in wastewater were described in detail, and the related adsorption mechanisms were systematically summarized and compared. The reusability of MOFs@aerogels in adsorption of pollutants was described. Finally, the optimization direction of the stability of MOFs in MOFs@aerogels, the matrix materials of aerogels, the application range and drying technology were proposed. It was proposed that improving the stability of MOFs@aerogels, exploring new matrix materials, expanding the application range of MOFs@aerogels, and exploring economical and green synthesis technologies would be the future research directions.

The guidance and control semi physical simulation system plays an important role in the development of guided weapons, and is an important way to verify the correctness of missile guidance and control system design and software design. The traditional Windows operating system has poor real-time performance, which brings many uncertainties to the hardware in the loop simulation test. Therefore, this paper uses the Windows+RTX scheme to complete the hardware and software design of the hardware in the loop simulation system. Through shared memory, the communication between Windows processes and RTX processes is realized to ensure the accuracy of data transmission and the real-time performance of the system. The final missile guidance and control semi physical simulation test results show that the designed semi physical simulation system is reasonable, and has good real-time performance, high reliability, and strong universality.

Objective To analyze the clinical phenotype and immunological characteristics of a patient with heterozygous mutation of PTEN and enrich the clinical phenotypes related to PTEN mutation. Methods A retrospective analysis of the clinical data of a patient with PTEN heterozygous mutation admitted to the Children's Hospital of Chongqing Medical University was conducted. Peripheral venous blood was extracted for medical whole-exome comprehensive detection, and the PTEN mutation was confirmed by Sanger sequencing. Flow cytometry was applied to detect the lymphocyte subsets and immunophenotype of the patient. The expression level of PTEN protein in peripheral blood mononuclear cells was detected by Western blot, and the healthy control was the patient's father. Results The patient was a boy of 1 year and 4 months, with macrocephaly (head circumference > P99), verrucous epidermal nevus, delayed psychomotor development and delayed language learning as the main manifestations. Gene sequencing revealed a de novo heterozygous mutation of PTEN c.388C > T(p.R130X). Reduced expression of PTEN protein was observed in peripheral blood mononuclear cells of the patient. For immunological characteristics, the IgA level mildly decreased(0.177 g/L), with increased counts of terminally differentiated memory CD4+ T cells, terminally differentiated memory CD8+ T cells, transitional B cells, but phosphorylation of PI3K/Akt/mTOR pathway in T cells was normal. The patient mainly manifested as PTEN hamartoma tumor syndrome related phenotype, without any classic activated phosphatidylinositol 3-kinase δ syndrome-like phenotype. Conclusions This patient has a de novo heterozygous mutation of PTEN c.388C > T(p.R130X), which has not been previously reported in China. This article could enrich clinicians' understanding of the disease and assist clinical diagnosis and treatment.

Safety protection design is a key problem to be considered in structural design. The study on mechanical characteristics of rolling lobe air spring（RLAS） under the extreme working condition lays an important foundation for its safety protection design. Considering the influence of outer diameter of rubber bellows along with the height of air spring, taking the radius of arc segment and inner cone angle of linear segment as the key design parameters, a novel mechanical model of rolling lobe air spring with safety protection design is established. The experimental results show that the maximum relative error of structural parameters of rolling lobe air spring is 11.9%, the relative error of static stiffness under different pressure in the extreme condition is less than 11% and the maximum relative error of load capacity is less than 6%, which all proves the correctness of mechanical model of RLAS. Force gain and stiffness gain are further proposed as quantitative characterization indexes of safety protection design, and the influence laws of key design parameters on mechanical characteristics and quantitative characterization indexes of rolling lob air spring under extreme condition are explored. The research results provide theoretical support for accurate calculation of safety protection capability of RLAS in the design stage.

This study focused on the fatigue and corrosion fatigue of maraging steel 18Ni (250). The 18Ni (250) samples were tested for axial fatigue in air and 3.5% NaCl solution. The effects of loading frequency and stress ratio on the fatigue strength of 18Ni (250) were studied. In air, the loading frequency was 10 Hz, and the stress ratio was 0.5. However, three loading methods were used in the 3.5% NaCl solution: (i) the loading frequency of 1 Hz and stress ratio of 0.5; (ii) the loading frequency of 1 Hz and stress ratio 0.1, and (iii) the loading frequency 5 Hz and stress ratio 0.5. The corrosion fatigue strength of samples in the 3.5% NaCl solution was 63.3% lower than that of the samples in air. The fractures in the samples were observed after the test.

This study focused on the fatigue and corrosion fatigue of maraging steel 18Ni (250). The 18Ni (250) samples were tested for axial fatigue in air and 3.5% NaCl solution. The effects of loading frequency and stress ratio on the fatigue strength of 18Ni (250) were studied. In air, the loading frequency was 10 Hz, and the stress ratio was 0.5. However, three loading methods were used in the 3.5% NaCl solution: (i) the loading frequency of 1 Hz and stress ratio of 0.5; (ii) the loading frequency of 1 Hz and stress ratio 0.1, and (iii) the loading frequency 5 Hz and stress ratio 0.5. The corrosion fatigue strength of samples in the 3.5% NaCl solution was 63.3% lower than that of the samples in air. The fractures in the samples were observed after the test.

The modulus of compressibility of muddy soil in Dawan District is low, and the equivalent value of modulus of compressibility within the calculated depth range of foundation settlement is generally less than 2.5MPa, which exceeds the value range of empirical coefficient calculation basis for settlement calculation in the specification, and has the characteristics of large settlement. This time, according to the measured data of a coastal foundation settlement in Dawan District, the maximum settlement is fitted with the hyperbolic method, and the theoretical value of the total settlement is calculated according to the Code for Design of Building Foundation (GB50007-2011). Based on this analysis, the fitting curve equation of the empirical coefficient of settlement calculation when the equivalent value of the compression modulus is 2.5~4.15MPa is given, and the recommended value of the empirical coefficient of settlement calculation when the equivalent value of the compression modulus is 1.5~2.5MPa is calculated, so as to improve the calculation deviation of the original formula.

Little research has been conducted to determine the thermal properties and phenomena of graphane and fluorographene. A clear understanding of the thermal problems involved is needed, which may provide a basis for further research on other material properties. In the present study, molecular dynamics simulations were performed to investigate the thermal properties of graphane and fluorographene and especially the phenomena involved, including thermal fluctuations and bending rigidities. Furthermore, comparisons of thermal properties and the phenomena involved were made computationally between pristine and functionalised graphene. The thermal fluctuations and bending rigidities were determined at different temperatures. The present study aims to provide a clear understanding of the thermal problems involved in hydrogenated and fluorinated graphene. The results indicated that while thermally excited ripples spontaneously appear in graphene, fully hydrogenated or fluorinated graphene is substantially unrippled due to their very high bending rigidities. There is no significant effect of thermal rippling throughout graphane and fluorographene due to their very high bending rigidities. However, partially hydrogenated or fluorinated graphene exhibits strong thermal fluctuations. Graphene behaves differently from graphane and fluorographene with regard to the dependence of bending rigidity on temperature. Furthermore, significant out-of-plane fluctuations may occur in partially fluorinated graphene. Thermal fluctuations of graphene are more sensitive to temperature than those of graphane and fluorographene.

The potential of methanol reforming systems to greatly improve productivity in chemical reactors has been limited, due in part, to the effect of mass transfer limitations on the production of hydrogen. There is a need to determine whether or not a microchannel reforming reactor system is operated in a mass transfer-controlled regime, and provide the necessary criteria so that mass transfer limitations can be effectively eliminated in the reactor. Three-dimensional numerical simulations were carried out using computational fluid dynamics to investigate the essential characteristics of mass transport processes in a microchannel reforming reactor and to develop criteria for determining mass transfer limitations. The reactor was designed for thermochemically producing hydrogen from methanol by steam reforming. The mass transfer effects involved in the reforming process were evaluated, and the role of various design parameters was determined for the thermally integrated reactor. In order to simplify the mathematics of mass transport phenomena, use was made of dimensionless numbers or ratios of parameters that numerically describe the physical properties in the reactor without units. The results indicated that the performance of the reactor can be greatly improved by means of proper design of catalyst layer thickness and through adjusting feed composition to minimize or reduce mass transfer limitations in the reactor. There is not an effective method to reduce channel dimensions if the flow rate remains constant, or to reduce fluid velocities if the residence time is kept constant. The rate of the reforming reaction is limited by mass transfer near the entrance of the reactor and by kinetics further downstream, when the heat transfer in the autothermal system is efficient. Finally, the criteria that can be used to distinguish between different mass transport and kinetics regimes in the reactor with a first-order reforming reaction were presented.

Protrusions can be used to improve the transport processes involved, but the causes of the phenomena are still incompletely understood. Computational fluid dynamics analyses are performed under different sets of circumstances to gain insights into the physics of heat and mass transfer processes in a protruded millisecond microchannel reactor, wherein a steam reforming reaction is proceeding and protrusions are used to improve the transport processes involved. Recommendations are made on how to optimize design for better reactor performance. Particular emphasis is placed on delineating the role of methanol-air equivalence ratio and channel length in reactor performance. The results indicate that the equivalence ratio and channel length must be adjusted as needed to minimize pressure drops and maximize production of hydrogen. Necessary adjustments to the equivalence ratio of methanol to air can be made to control the maximum reactor temperature within certain needed limits. The short-channel design may be preferred over the long-channel design in order to simultaneously achieve low pressure drops and sufficiently high conversions in the reactor. Expectable compromises have to be made between hydrogen productivity and pressure drop.

The present study focuses upon the physics of heat and mass transfer processes in a protruded millisecond microchannel reactor, wherein a steam reforming reaction is proceeding and protrusions are used to improve the transport processes involved. Parametric analysis of the reactor system is carried out using a three-dimensional numerical model that is sufficiently detailed to delineate the role of geometric features and operation conditions in reactor performance. Computational fluid dynamics analyses are performed under different sets of circumstances. In analysing the mechanisms involved in the intensified processes, account is taken of the factors that may influence the reactor performance. New insights into the physics of the processes are presented, with recommendations on how to optimize reactor design for better performance. The results indicate that the flow rates and feed compositions must be adjusted as needed to maximize production of hydrogen and minimize pressure drops. Protrusions are very effective in improving the transport processes involved without greatly impairing hydraulic performance. Methanol can be converted effectively to hydrogen due to the successive continuous interruptions in the presence of hemispherical protrusions. Necessary adjustments to the molar ratio of steam to methanol can be made to control the maximum reactor temperature within certain needed limits. Protrusions can be used to improve the conversion and productivity due to enhanced heat and mass transfer, as they behave as a baffle to direct flow of the reforming process flow stream.

In spite of significant efforts to investigate the ability of hydrogenated and fluorinated graphene to conduct heat, little research has focused particularly upon their other thermal properties, such as thermal contraction and heat capacity, which have implications for the development of thermal nanotechnology. In an attempt to determine these thermal properties, a few experiments have been carried out, with rather conflicting results. In the present study, calculations were performed using molecular dynamics to investigate the thermal properties of graphane and fluorographene and especially the phenomena involved. The thermal expansion coefficients and heat capacities of the two-dimensional materials were determined at different temperatures. The results indicated that graphane is thermally contracted more significantly than graphene. The calculated molar heat capacity at constant volume is about 25.00 J/(mol·K) for graphene and about 29.26 J/(mol·K) for graphane. The specific heat capacity of fluorographene is always lower than that of graphane. A negative relationship does exist between the binding energy and the temperature.

Flow of a fluid past a body is a very complicated phenomenon. Computational fluid dynamics is used for studying the characteristics of flow past an array of hemispherical protrusions that is disposed on the wall surfaces of a millisecond microchannel reactor. Protrusions can be used to improve the transport processes involved, but the causes of the phenomena are still incompletely understood. Parametric analyses are performed under different sets of circumstances to delineate the role of geometric features and operation conditions in reactor performance. Dimensionless quantities are used to simplify the characterization of the reactor system with multiple interacting transport phenomena. The mechanisms involved in the intensified processes are analysed, and performance improvement recommendations are presented. The results indicate that the protruded reactor behaves effectively and good yields can be obtained with only milliseconds residence of the mixtures within the channels. The reactor offers the unique advantage for hydrogen production from methanol in that process intensification is realized while preserving the energy balance between the exothermic and endothermic processes. However, the flow rates must be adjusted as needed to maximize production of hydrogen and minimize pressure drops. The momentum diffusivity is more dominant around the protrusion regions than in the other regions. The thermal diffusivity is more dominant in the protruded channels than in the flat channels. The results have implications for hydrogen production and beyond for the study of transport phenomena in microchemical systems.

Computational modelling for microchannel reactor design was conducted in the attempt to fully understand autothermal reforming phenomena in continuous flow reactors. The effects of pressure and flow rate on the efficiency and performance were evaluated by performing computational fluid dynamics under different design conditions. The reactor efficiency and performance were assessed by means of the reactant conversion, product yield, reaction rate, hydrogen productivity, and output power. Recommendations for designing an autothermal reforming system were made and strategies for performing efficient operation were set forth. The results indicated that the pressure and flow rate set strict limits on operation, and there is a trade-off between high productivity and low conversion. The pressure and flow rate play competing roles in the reactor efficiency and performance. Lower pressures and flow rates can increase the conversion and yield, but higher pressures and flow rates can significantly improve the hydrogen productivity and output power, which is essential to the success of start-up and acceleration of the downstream equipment. There may exist an optimum pressure and flow rate in terms of both efficiency and performance. The calculated output power is of the order of thousands of kilowatts per cubic meter.

Computational fluid dynamics uses numerical methods and algorithms to solve and analyse problems that involve fluid flows. Computers may be used to perform the calculations required to simulate the interaction of liquids and gasses with a surface defined by boundary conditions. Thermodynamics is the science of the relationship between heat, work, temperature, and energy. Computational modelling for microchannel reactor design was performed to investigate the effects of various factors on the efficiency and performance of an autothermal reforming system. The yield and productivity from the chemical process were determined by performing computational fluid dynamics and thermodynamic analysis. Strength and weakness were assessed under different reaction conditions. Design recommendations were provided and operation strategies were mapped out. The results indicated that operation at millisecond contact times is feasible, but optimisation of reaction conditions is necessary to balance efficiency and performance. The conversion to hydrogen is influenced greatly by the feed composition, which must be controlled precisely within certain needed limits to maximize the yield and productivity from the autothermal reforming process while avoiding the problems of combustion or explosion. Additionally, the efficiency difference between feed compositions is determined by thermodynamic analysis. The calculated output power of the autothermal reforming reactor is of the order of thousands of kilowatts per cubic meter.

For fault diagnosis of rolling bearings,a new feature extraction strategy based on short time Fourier transform（ STFT） and bag of wordss（ BOW） is proposed. Based on the generate mechanism of bearing fault,the different bearing vibration signals have relevant energy distribution. But in the factory,some factors like signal interference or environment noise will destroy the energy distribution. When using BOW,it regards the distribution of energy in frequency domain each time frame as a word,so segments of signal will be documents which are made up of many words. It shows the energy distribution directly in data perspective. Then,with the new features and SVM classifier,the results of fault diagnosis can be known. At last,effectiveness of the proposed method is verified,vibration from SQI- MFS platform and CWRU platform are analyzed. The results in experiments shows that this method is better than RMS and WE&WEE. So the new feature can be used in fault diagnosis area.

A combustion air stream is introduced tangentially into the interior of a premix burner by means of a swirl producer, and is mixed with fuel. At the burner outlet, the vortex flow which arises bursts open at a sudden change of cross section, with the initiation of a back-flow zone which serves to stabilize a flame in the operation of the burner. Although premix burners make possible an operation with very low pollutant emissions, they often operate dangerously near to the extinction limit of the flame. Cavity structures have been designed for the purpose of improving flame stability. However, the precise mechanism by which the cavity method provides increased flame stability remains unclear. This study relates to the combustion characteristics and flame stability of a micro-structured cavity-stabilized burner. Computational fluid dynamics simulations are conducted to gain insights into burner performance such as reaction rates, species concentrations, temperatures, and flames. Factors affecting combustion characteristics and flame stability are determined. Design recommendations are provided. The results indicate that the thermal conductivity of the burner walls plays a vital role in flame stability. Improvements in flame stability are achievable by using walls with anisotropic thermal conductivity. Heat-insulating materials are favored to minimize external heat losses. Burner dimensions greatly affect flame stability. The inlet velocity of the mixture is a critical factor in assuring flame stability within the cavity-stabilized burner. There is a narrow range of inlet velocities that permit sustained combustion within the cavity-stabilized burner. There are issues of efficiency loss for fuel-rich cases. Burners with large dimensions lead to a delay in flame ignition and may cause blowout. The combustion is stabilized by recirculation of hot combustion products induced by the cavity structure.

Direct oxidation of fuels such as methanol in proton-exchange membrane fuel cells at practical current densities with acceptable catalyst loadings is not as economically attractive as conversion of methanol fuel to a hydrogen-rich mixture of gases via steam reforming and subsequent electrochemical conversion of the hydrogen-rich fuel stream to direct current in the fuel cell. The potential of methanol reforming systems to greatly improve productivity in chemical reactors has been limited, due in part, to the effect of mass transfer limitations on the production of hydrogen. There is a need to determine whether or not a microchannel reforming reactor system is operated in a mass transfer-controlled regime, and provide the necessary criteria so that mass transfer limitations can be effectively eliminated in the reactor. Three-dimensional numerical simulations were carried out using computational fluid dynamics to investigate the essential characteristics of mass transport processes in a microchannel reforming reactor and to develop criteria for determining mass transfer limitations. The reactor was designed for thermochemically producing hydrogen from methanol by steam reforming. The mass transfer effects involved in the reforming process were evaluated, and the role of various design parameters was determined for the thermally integrated reactor. In order to simplify the mathematics of mass transport phenomena, use was made of dimensionless numbers or ratios of parameters that numerically describe the physical properties in the reactor without units. The results indicated that the rate of the reforming reaction is limited by mass transfer near the entrance of the reactor and by kinetics further downstream, when the heat transfer in the autothermal system is efficient. There is not an effective method to reduce channel dimensions if the flow rate remains constant, or to reduce fluid velocities if the residence time is kept constant. The performance of the reactor can be greatly improved by means of proper design of catalyst layer thickness and through adjusting feed composition to minimize or reduce mass transfer limitations in the reactor. Finally, the criteria that can be used to distinguish between different mass transport and kinetics regimes in the reactor with a first-order reforming reaction were presented.

The most important industrial method for the production of hydrogen is the catalytic steam reforming process. Many attempts have been made to improve heat transfer for thermally integrated microchannel steam reforming reactors. However, the mechanisms for the effects of design factors on heat transfer characteristics are still not fully understood. This study relates to a thermochemical process for producing hydrogen by the catalytic endothermic reaction of methanol with steam in a thermally integrated microchannel reforming reactor. Computational fluid dynamics simulations are conducted to better understand the consumption, generation, and exchange of thermal energy between endothermic and exothermic processes in the reactor. The effects of wall heat conduction properties and channel dimensions on heat transfer characteristics and reactor performance are investigated. Thermodynamic analysis is performed based on specific enthalpy to better understand the evolution of thermal energy in the reactor. Design recommendations are made to improve thermal performance for the reactor. The results indicate that reaction heat flux profiles are considerably affected by channel dimensions. The peak reaction heat flux increases with the channel dimensions while maintaining the flow rates. The change in specific enthalpy is positive for the exothermic reaction and negative for the endothermic reaction. The change in specific sensible enthalpy is always positive. The thermal conductivity of the channel walls is fundamentally important. Materials with high thermal conductivity are preferred for the channel walls. Thermally conductive ceramics and metals are well-suited. Wall materials with poor heat conduction properties degrade the reactor performance.

The unique one-dimensional structure and concomitant properties endow carbon nanotubes with special natures, rendering them with unlimited potential in nanotechnology-associated applications. The increasing popularity of carbon nanotubes has created a demand for greater scientific understanding of the characteristics of thermal transport in nanostructured materials. However, the effects of impurities, misalignments, and structure factors on the thermal conductivity of carbon nanotube films and fibers are still poorly understood. Carbon nanotube films and fibers were produced, and the parallel thermal conductance technique was employed to determine the thermal conductivity. The effects of carbon nanotube structure, purity, and alignment on the thermal conductivity of carbon films and fibers were investigated to understand the characteristics of thermal transport in the nanostructured material. The importance of bulk density and cross-sectional area was determined experimentally. The results indicated that single-walled carbon nanotube films and fibers generally have high thermal conductivity. The presence of non-carbonaceous impurities degrades the thermal performance due to the low degree of bundle contact. The prepared carbon nanotube films and fibers are very efficient at conducting heat. The structure, purity, and alignment of carbon nanotubes play a fundamentally important role in determining the heat conduction properties of carbon films and fibers. The thermal conductivity may present power law dependence with temperature. The specific thermal conductivity decreases with increasing bulk density. The specific thermal conductivity of carbon nanotube fibers is significantly higher than that of carbon nanotube films due to the increased degree of bundle alignment. At room temperature, a maximum specific thermal conductivity is obtained but Umklapp scattering occurs.

The heterogeneous and homogeneous combustion-based homogeneous charge compression ignition of fuel-lean methane-air mixtures over alumina-supported platinum catalysts was investigated experimentally and numerically in free-piston micro-engines without ignition sources. Single-shot experiments were carried out in the purely homogeneous and coupled heterogeneous and homogeneous combustion modes, involved temperature measurements, capturing the visible combustion image sequences, exhaust gas analysis, and the physicochemical characterization of catalysts. Simulations were performed with a two-dimensional transient model that includes detailed heterogeneous and homogeneous chemistry and transport, leakage, and free-piston motion to gain physical insight and to explore the heterogeneous and homogeneous combustion characteristics. The micro-engine performance concerning combustion efficiency, mass loss, energy density, and free-piston dynamics was investigated. The results reveal that heterogeneous reactions cause earlier ignition, which is very favourable for the micro-device. Both purely homogeneous and coupled heterogeneous and homogeneous combustion of methane-air mixtures in a narrow cylinder with a diameter of 3 mm and a height of approximately 0.3 mm are possible. Heat losses result in higher mass losses. The coupled heterogeneous and homogeneous mode can not only significantly improve the combustion efficiency, in-cylinder temperature and pressure, output power and energy density, but also reduce the mass loss because of its lower compression ratio and less time spent around the top dead centre and during the expansion stroke, indicating that this coupled mode is a promising combustion scheme for micro-engines.

Flame stabilization is a common problem in small-scale combustion systems. However, the fuel-air mixture flow pattern, including any recirculation, is critical to achieving flame stability. In the present study, numerical simulations are conducted to understand the mechanisms of flame stabilization in heat-recirculating continuous flow reactors. The essential factors affecting combustion characteristics and flame stability are determined in order to obtain design insights. The results indicate that the wall thermal conductivity, flow velocity, equivalence ratio, and exterior heat losses are important factors in determining the energy efficiency of the reactor. There is an optimum wall thermal conductivity in terms of flame stability. The system with a moderate wall thermal conductivity will be most robust against the surrounding conditions. Excess enthalpy combustion can occur in an efficient and rapid manner, resulting from the injection of free radicals and heat produced by the catalytic reaction. The design incorporates the best features of both catalytic combustion and thermal flame methods. The system is essentially free of mass transfer limitations. Stable operation of the system is limited to a relatively wide flow regime, and the flow velocity is critical to achieving flame stability. Blowout shifts homogeneous combustion downstream significantly without substantially reducing the reaction rate. Both chemical and thermal environments are improved with the catalytically stabilized combustion method and the heat-recirculating structure.

Terahertz waves offer advantages for nondestructive detection of hidden objects/defects in materials, as they can penetrate most optically-opaque materials. However, existing terahertz inspection systems face throughput and accuracy restrictions due to their limited imaging speed and resolution. Furthermore, machine-vision-based systems using large-pixel-count imaging encounter bottlenecks due to their data storage, transmission and processing requirements. Here, we report a diffractive sensor that rapidly detects hidden defects/objects within a 3D sample using a single-pixel terahertz detector, eliminating sample scanning or image formation/processing. Leveraging deep-learning-optimized diffractive layers, this diffractive sensor can all-optically probe the 3D structural information of samples by outputting a spectrum, directly indicating the presence/absence of hidden structures or defects. We experimentally validated this framework using a single-pixel terahertz time-domain spectroscopy set-up and 3D-printed diffractive layers, successfully detecting unknown hidden defects inside silicon samples. This technique is valuable for applications including security screening, biomedical sensing and industrial quality control.

The most efficient and stable combustion occurs in a catalytic reactor when the burning mixture is in contact with the catalyst for a sufficiently long period. When the contract period is too short, insufficient energy is generated adjacent to the catalyst surface to sustain combustion in the main or free stream. This study is focused mainly upon the essential combustion characteristics of propane-air mixtures in flow tube reactors with a heat-recirculating structure. Computational fluid dynamics simulations are performed to gain a greater understanding of the mechanisms of flame stabilization. The essential factors affecting flame stability and combustion characteristics are determined in order to obtain design insights. The results indicate that in order to meet the emission level requirements, for industrial low emission gas turbine engines, staged combustion is required in order to minimise the quantity of the oxides of nitrogen produced. The combustion catalyst has several desirable characteristics: they are capable of minimizing nitrogen oxides emission and improving the pattern factor. Operating the combustion process in a very lean condition, namely high excess air, is one of the simplest ways of achieving lower temperatures and hence lower nitrogen oxides emissions. The use of a catalytic combustor offers the advantage that all of the fuel can be oxidized therein, resulting in ultra-low nitrogen oxides emissions and low carbon monoxide and unburned hydrocarbon levels. In mass transfer controlled catalytic reactions, one cannot distinguish between a more active catalyst and a less active catalyst because the intrinsic catalyst activity is not determinative of the rate of reaction. It is possible to achieve essentially adiabatic combustion in the presence of a catalyst at a reaction rate many times greater than the mass transfer limited rate. The maximum achievable velocity depends on flow conditions and catalyst parameters such as type, monolith cell size, and web thickness.

Heat transfer and thermodynamic analysis are performed using computational fluid dynamics and chemical kinetics to investigate the synthesis gas production processes in chemical reactors with integrated heat exchangers by steam reforming. The change of thermal energy in the reactor is fully described in order to analyze the influences of fluid velocity, solid thermal properties, and flow arrangement on the thermal behavior of the reactor. The evolution of energy is discussed in terms of reaction heat flux, and thermodynamic analysis of the oxidation and reforming processes is performed in terms of enthalpy changes. The results indicate that while the net sensible enthalpy change is always positive in the reactor, the net enthalpy change for the endothermic and exothermic reactions is positive and negative, respectively. The wall thermal conductivity plays a significant role in determining the efficiency and operation of the autothermal system. The parallel flow design is advantageous for purposes of avoiding localized hot spots and enhancing heat transfer. The change in enthalpy is vital to the endothermic and exothermic reactions. The thermal behavior of the reactor system depends upon the thermal properties of the walls. The change in flow arrangement significantly affects the reaction heat flux in the reactor. The endothermic reforming reaction can proceed efficiently and rapidly if the wall thermal conductivity is high. The reaction heat flux for the endothermic and exothermic processes is negative and positive, respectively. The wall heat conduction effect accompanying temperature changes is of great importance to the autothermal design and self-sustaining operation of the reactor.

To make better use of agricultural residues and solve the problem of residues pollution, it is necessary to carry out regional management, which means spatial planning of the entire region is essential. This study developed a methodology based on GIS for determining the suitable locations, optimal sizes and number of biogas plants for the entire region while meeting the conditions that all biomass can be collected. Based on the optimization of transportation distance, the nearest facility model and the modified location allocation model were used to obtain the correspondence between plants and supply points, the transportation path and the plants’ capacity under different numbers of plants. Based on economic optimization, the economic model was constructed to calculate the total cost of different numbers of biogas plants and the optimal number was obtained after comparing. The cross path was adjusted for the selected plan to ensure that there was no crossover in the plants’ collection area. This approach was applied (as a case study) in Funan County, Anhui Province. Based on the existing results, the optimal construction number of biogas plants in the region was 9.

Anthracyclines such as doxorubicin (Dox) are effective chemotherapeutic agents; however, their use is hampered by subsequent cardiotoxicity risk. Our understanding of cardiomyocyte protective pathways activated following anthracycline-induced cardiotoxicity (AIC) remains incomplete. Insulin-like growth factor binding protein (IGFBP) 3 (Igfbp-3), the most abundant IGFBP family member in the circulation, is associated with effects on the metabolism, proliferation, and survival of various cells. Whereas Igfbp-3 is induced by Dox in the heart, its role in AIC is ill-defined. We investigated molecular mechanisms as well as systems-level transcriptomic consequences of manipulating Igfbp-3 in AIC using neonatal rat ventricular myocytes and human-induced pluripotent stem cell-derived cardiomyocytes. Our findings reveal that Dox induces the nuclear enrichment of Igfbp-3 in cardiomyocytes. Furthermore, Igfbp-3 reduces DNA damage, impedes topoisomerase IIβ expression (Top2β) which forms Top2β-Dox-DNA cleavage complex leading to DNA double-strand breaks (DSB), alleviates detyrosinated microtubule accumulation-a hallmark of increased cardiomyocyte stiffness and heart failure-and favorably affects contractility following Dox treatment. These results indicate that Igfbp-3 is induced by cardiomyocytes in an effort to mitigate AIC.