Thermogravimetric characteristics of corn straw and bituminous coal copyrolysis based the ilmenite oxygen carriers

Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass spectrometry.The results reveal that the participation of OCs weakens the devolatilization intensity of co-pyrolysis.When the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic effects.The fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).

Joint Estimation of Carrier Frequency and Phase Offset Based on Pilot Symbols in Quasi-Constant Envelope OFDM Satellite Systems

Spectral efficiency and energy efficiency are two important performance indicators of satellite systems. The Quasi-Constant Envelope Orthogonal Frequency Division Multiplexing(QCE-OFDM) technique can achieve both high spectral efficiency and low peak-to-average power ratio(PAPR). Therefore, the QCE-OFDM technique is considered as a promising candidate multi-carrier technique for satellite systems. However, the Doppler effect will cause the carrier frequency offset(CFO), and the non-ideal oscillator will cause the carrier phase offset(CPO) in satellite systems. The CFO and CPO will further result in the bit-error-rate(BER) performance degradation. Hence, it is important to estimate and compensate the CFO and CPO. This paper analyzes the effects of both CFO and CPO in QCE-OFDM satellite systems. Furthermore, we propose a joint CFO and CPO estimation method based on the pilot symbols in the frequency domain. In addition, the optimal pilot symbol structure with different pilot overheads is designed according to the minimum Cramer-Rao bound(CRB) criterion. Simulation results show that the estimation accuracy of the proposed method is close to the CRB.

Regulation of the quantum barrier and carrier transport toward high-efficiency quasi-2D Dion-Jacobson tin perovskite solar cells

Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.

Optimizing the sulfur-resistance and activity of perovskite oxygen carrier for chemical looping dry reforming of methane

Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance.

Clinical Analysis and Mental Health Survey of Hemophilia Carriers:a Cross-sectional Study

Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being.

Blind Channel Identification for Cyclic-Prefixed MIMO-OFDM Systems with Virtual Carriers

This paper applies the repetition index scheme(RIS)to the channel identification of cyclic prefixed(CP)multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM)systems with virtual carriers(VCs)in the environment of the number of receive antennas being no less than that of transmit antennas.The VCs will cause a rank deficiency problem in computing the subspace information.With the subcarrier mapping matrix,the received signal is simplified to remove the rank deficiency.We use the RIS scheme to generate many times of equivalent symbols so the channel identification can converge with few received OFDM blocks.The RIS scheme will convert the white noise into non-white noise.With the Cholesky factorization,a noise whitening technique is developed to turn the non-white noise back to white noise.We further analyze the necessary conditions of identifiability of channel estimation.Simulations are performed to show the superiority of the proposed method.

Atomic Ni directional-substitution on ZnIn_(2)S_(4) nanosheet to achieve the equilibrium of elevated redox capacity and efficient carrier-kinetics performance in photocatalysis

It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced into the lattice of hexagonal ZnIn_(2)S_(4) nanosheets(Ni/ZnIn_(2)S_(4))via directionalsubstituting Zn atom with the facile hydrothermal method.The electronic structure calculations indicate that the introduction of Ni atom effectively extracts more electrons and acts as active site for subsequent reduction reaction.Besides the optimized light absorption range,the elevation of Efand ECBendows Ni/ZnIn_(2)S_(4) photocatalyst with the increased electron concentration and the enhanced reduction ability for surface reaction.Moreover,ultrafast transient absorption spectroscopy,as well as a series of electrochemical tests,demonstrates that Ni/ZnIn_(2)S_(4) possesses 2.15 times longer lifetime of the excited charge carriers and an order of magnitude increase for carrier mobility and separation efficiency compared with pristine ZnIn_(2)S_(4).These efficient kinetics performances of charge carriers and enhanced redox capacity synergistically boost photocatalytic activity,in which a 3-times higher conversion efficiency of nitrobenzene reduction was achieved upon Ni/ZnIn_(2)S_(4).Our study not only provides in-depth insights into the effect of atomic directional-substitution on the kinetic behavior of photogenerated charges,but also opens an avenue to the synchronous optimization of redox capacity and carrier-kinetics performance for efficient solar energy conversion.

The design of monitoring communication system Based on Power line carrier

The design of the power line carrier communication system was introduced in this paper,DSP was adopted as the hardware platform to complete the core task.DSP sending terminal delivered the collecting data to the DSP receiving terminal through the power line carrier, and the DSP receiving terminal send the data to PC through a serial port.The design improved the power line carrier communication system and the data transmission became faster and more reliable.The experiment results showed that the PER of the receiving data is less than 0.4%, which satisfied the power line carrier communication requirement Our design is feasible and effective.

Influence of Bow Design on Ice Resistance for Arctic LNG Carriers

In order to understand the influence of bow shape on ice resistance and provide guidelines for hull line design in the early design stage,an investigation of the impact of bow shape on ice resistance for the Arctic LNG carriers is carried out based on semi-empirical methods.Firstly,some typical semi-empirical formulas developed for ice resistance estimation of cargo carriers in different ice conditions are summarized.Then,formulas appropriate for ice resistance estimation of Arctic LNG carriers under different ice conditions are verified according to the result comparison between semi-empirical formulas and experimental tests.The comparison result indicates that the Lindqvist formula is appropriate for ice resistance estimation in level ice conditions,Zuev and Dobrodeev formula for ice resistance estimation in broken ice conditions,and Dobrodeev formula for ice resistance estimation in brash ice conditions.After that,the parameters considered in the selected formulas are summarized,and the influence of critical parameters on ice resistance is analyzed.Some parameters describing the ship's bow shape characteristic like ship breadth,waterline angle and stem angle greatly influence the ice resistance.Ice resistance increases with both the growth of ship breadth under all ice conditions and the growth of stem angle in level ice and broken ice conditions while ice resistance decreases with the development of waterline angle under all ice conditions.Finally,the optimization of the bow shape is discussed,and an optimized bow shape with both a large waterline angle and low stem angle is proposed.The optimized bow shape can decrease ice resistance by 9.9%in the level ice condition and reduce ice resistance by 11.3%in the brash ice condition.

CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier

Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.

Comprehensive study of the ultrafast photoexcited carrier dynamics in Sb_(2)Te_(3)–GeTe superlattices

Chalcogenide superlattices Sb_(2)Te_(3)-GeTe is a candidate for interfacial phase-change memory(iPCM) data storage devices.By employing terahertz emission spectroscopy and the transient reflectance spectroscopy together,we investigate the ultrafast photoexcited carrier dynamics and current transients in Sb_(2)Te_(3)-GeTe superlattices.Sample orientation and excitation polarization dependences of the THz emission confirm that ultrafast thermo-electric,shift and injection currents contribute to the THz generation in Sb_(2)Te_(3)-GeTe superlattices.By decreasing the thickness and increasing the number of GeTe and Sb_(2)Te_(3) layer,the interlayer coupling can be enhanced,which significantly reduces the contribution from circular photo-galvanic effect(CPGE).A photo-induced bleaching in the transient reflectance spectroscopy probed in the range of~1100 nm to~1400 nm further demonstrates a gapped state resulting from the interlayer coupling.These demonstrates play an important role in the development of iPCM-based high-speed optoelectronic devices.

Mitochondrial carrier homolog 2 increases malignant phenotype of human gastric epithelial cells and promotes proliferation,invasion,and migration of gastric cancer cells

BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells.

Optimal Preview Control for Automatic Carrier Landing System of Carrier-Based Aircraft with Air Wake

Carrier-based aircraft carrier landing is a special kind of tracking control problem and not suitable for classical control methods,which may miss the desired performance or result in overdesign.Therefore,we present an optimal preview control for automatic carrier landing system(ACLS)by using state information of system,as well as future reference information,which can avoid the shortcomings of classical control methods.Since the flight performance of carrier-based aircraft is disturbed by air wake when the aircraft flies near the area of carrier stern,we design a disturbance rejection strategy to ensure that aircraft track the glide path with high precision and robustness.Further,carrier-based aircraft is a complex nonlinear system.However,the nonlinear model of carrier-based aircraft can be linearized at equilibrium landing state and decoupled into the longitudinal model and the lateral model.Therefore,an optimal preview control system is designed.The simulation results of a carrier-based aircraft show that the optimal preview control system can effectively suppress air wake.Tracking accuracy of optimal preview controller is higher than that of the proportional integral differential(PID)control system.

ESTIMATION OF CARRIER FREQUENCY OFFSETS FOR MIMO SYSTEMS WITH DISTRIBUTED TRANSMIT ANTENNAS

The problem of estimating the carrier frequency offsets in Multiple-Input Multiple-Output (MIMO) systems with distributed transmit antennas is addressed. It is supposed that the transmit antennas are distributed while the receive antennas are still centralized, and the general case where both the time delays and the frequency offsets are possibly different for each transmit antenna is considered. The channel is supposed to be frequency flat, and the macroscopic fading is also taken into consideration. A carrier frequency offset estimator based on Maximum Likelihood (ML) is proposed, which can separately estimate the frequency offset for each transmit antenna and exploit the spatial diversity. The Cramer-Rao Bound (CRB) for synchronous MIMO (i.e., the time delays for each transmit antenna are all equal) is also derived. Simulation results are given to illustrate the per- formance of the estimator and compare it with the CRB. It is shown that the estimator can provide satisfactory frequency offset estimates and its performance is close to the CRB for the Signal-to-Noise Ratio (SNR) below 20dB.

THE PERFORMANCE OF MT-CDMA SYSTEM IN THE PRESENCE OF CARRIER FREQUENCY OFFSET

In this letter,the sensitivity of an uplink Multi-Tone Code-Division Multiple Access (MT-CDMA) system to the Carrier Frequency Offset (CFO) is investigated. The analytical expression for the Bit Error Rate (BER) of uplink MT-CDMA in the presence of CFO is derived in a multipath Rayleigh fading channel which is verified through simulations. Both Maximal Ratio Combining (MRC) and Equal Gain Combining (EGC) are considered in combining multipath signals in the analysis. It is found that the BER performance can be improved with the number of multipath increasing in the presence of CFO.

New Insight into the Development of Oxygen Carrier Materials for Chemical Looping Systems

Chemical looping combustion （CLC） and chemical looping reforming （CLR） are innovative technologies for clean and efficient hydrocarbon conversion into power, fuels, and chemicals through cyclic redox reac- tions. Metal oxide materials play an essential role in the chemical looping redox processes. During reduc- tion, the oxygen carriers donate the required amount of oxygen ions for hydrocarbon conversion and product synthesis. In the oxidation step, the depleted metal oxide oxygen carriers are replenished with molecular oxygen from the air while heat is released. In recent years, there have been significant advances in oxygen carrier materials for various chemical looping applications. Among these metal oxide materials, iron-based oxygen carriers are attractive due to their high oxygen-carrying capacity, cost ben- efits, and versatility in applications for chemical looping reactions. Their reactivity can also be enhanced via structural design and modification. This review discusses recent advances in the development of oxy- gen carrier materials and the mechanisms of hydrocarbon conversion over these materials. These advances will facilitate the development of oxygen carrier materials for more efficient chemical looping technology applications.

Nanoparticles for the treatment of spinal cord injury

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

Efficient and Stable Photoassisted Lithium‑Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active photocathodes.Present work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic nanocrystals.When employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging process.Additionally,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky contact.Benefiting from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1)at 0.2 A g^(−1)under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 cycles.These results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

Evaluation of effective carrier system and function on hydrocarbon accumulation in Gaoyou Sag,Subei Basin,China

Effective carrier system comprises carrier beds which transport hydrocarbons. The spatial and temporal effectiveness of carrier system is identified according to the relevance of hydrocarbon show, hydrocarbon inclusion and sealing ability of fault to hydrocarbons distribution, together with matching relation of activity history of fault and hydrocarbon generation history of source rock. On the basis of the above considerations, transporting ability of effective carrier system can be evaluated using parameters such as fluid potential, porosity and permeability, spatial coefficient of effective pathway as well as activity rate of fault. Additionally, a new concept of＂transporting threshold porosity＂ was proposed. Five styles of effective carrier systems were established in Gaoyou Sag, displaying either layered or zonal distribution characteristics, and transporting time ranges from the sedimentary time of Ezdz to early stage of sanduo uplift. Effective carrier systems can be described to be lowly-efficient and highly-efficient. Major faults （convex or steep fault plane） with activity rate greater than 20 m/Ma and structure ridges of sand layers with spatial coefficient of effective pathway greater than 25% are defined to be highly-efficient carrier beds. Hydrocarbons are concentrated around high-efficient carrier beds and E1 f traps of northern shanian area are predicted to have great potential.

ICI elimination of M-band wavelet multi-carrier modulation system

To solve the inter carrier interference （ICI） elimination problem of an M-band wavelet multi-carrier modulation system, this paper analyzes the principle of the ICI caused by the Doppler frequency shift and its mathematical expression based on the M-band wavelet multi-carrier modulation system model. Through the analysis of the mathematical expression and combining with the perfect reconstruction conditions of the filter banks, we propose the design conditions of an M-band filter to reduce and eliminate the ICI. The impulse response model of the filter design conditions and an iterative algorithm is also established. The simulation results show that the proposed ICI reduction and elimination methods can effectively improve the system performance.