Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension system.This paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a tractor.Finally,the tractor is prototyped and assembled,and ploughing tests are carried out.The ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution mode.Compared with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy consumption.This study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

Current improvement in substrate structured Sb2S3 solar cells with MoSe2 interlayer

Sb2S3 solar cells with substrate structure usually suffer from pretty low short circuit current(JSC)due to the defects and poor carrier transport.The Sb2S3,as a one-dimensional material,exhibits orientation-dependent carrier transport property.In this work,a thin MoSe2 layer is directly synthesized on the Mo substrate followed by depositing the Sb2S3 thin film.The x-ray diffraction(XRD)patterns confirm that a thin MoSe2 layer can improve the crystallization of the Sb2S3 film and induce(hk1)orientations,which can provide more carrier transport channels.Kelvin probe force microscopy(KPFM)results suggest that this modified Sb2S3 film has a benign surface with less defects and dangling bonds.The variation of the surface potential of Sb2S3 indicates a much more efficient carrier separation.Consequently,the power conversion efficiency(PCE)of the substrate structured Sb2S3 thin film solar cell is improved from 1.36%to 1.86%,which is the best efficiency of the substrate structured Sb2S3 thin film solar cell,and JSC significantly increases to 13.6 mA/cm^2.According to the external quantum efficiency(EQE)and C-V measurements,the modified crystallization and elevated built-in electric field are the main causes.

Methods for Derivation of Density Matrix of Arbitrary Multi-Mode Gaussian States from Its Phase Space Representation

We present a method for derivation of the density matrix of an arbitrary multi-mode continuous variable Gaussian entangled state from its phase space representation.An explicit computer algorithm is given to reconstruct the density matrix from Gaussian covariance matrix and quadrature average values.As an example,we apply our method to the derivation of three-mode symmetric continuous variable entangled state.Our method can be used to analyze the entanglement and correlation in continuous variable quantum network with multi-mode quantum entanglement states.

Rapid Structure-Based Screening Informs Potential Agents for Coronavirus Disease(COVID-19)Outbreak

Coronavirus Disease 2019(COVID-19),caused by the novel coronavirus,has spread rapidly across China.Consequently,there is an urgent need to sort and develop novel agents for the prevention and treatment of viral infections.A rapid structure-based virtual screening is used for the evaluation of current commercial drugs,with structures of human angiotensin converting enzymeⅡ(ACE2),and viral main protease,spike,envelope,membrane and nucleocapsid proteins.Our results reveal that the reported drugs Arbidol,Chloroquine and Remdesivir may hinder the entry and release of virions through the bindings with ACE2,spike and envelope proteins.Due to the similar binding patterns,NHC(β-d-N4-hydroxycytidine)and Triazavirin are also in prospects for clinical use.Main protease(3 CLpro)is likely to be a feasible target of drug design.The screening results to target 3 CLpro reveal that Mitoguazone,Metformin,Biguanide Hydrochloride,Gallic acid,Caffeic acid,Sulfaguanidine and Acetylcysteine seem be possible inhibitors and have potential application in the clinical therapy of COVID-19.

Continuous Variable Quantum Teleportation in Beam-Wandering Modeled Atmosphere Channel

We investigate the continuous variable quomtum teleportation in atmosphere channels. The beam-wandering mode/is employed to analyze the teleportation of the unknown single-mode coherent state. Two methods, one is deterministic by increasing the aperture size of the detecting device and one is probabilistic by entanglement distillation, are proposed to improve the teleportation fidelity in the presence of atmosphere noises.

N,P Co-Doped Carbon Dots as Multifunctional Fluorescence Nano-Sensor for Sensitive and Selective Detection of Cr(Ⅵ) and Ascorbic Acid

It is particularly important to monitor Cr(Ⅵ)for its high toxicity.In this paper,a novel,simple,low-cost and"on-off-on"fluorescence sensor of carbon dots doped with nitrogen and phosphorus(N,P-CDs)was developed via one-step hydrothermal method for highly sensitive and good selective detection of Cr(Ⅵ)and ascorbic acid(AA).The prepared N,P-CDs exhibited the ability for detection of Cr(Ⅵ)based on the inner filter effect(IFE)and static quenching.Under optimized conditions,the fluorescence quenching efficiency of N,P-CDs showed a good linear correlation with Cr(Ⅵ)concentration ranged from0.68 to 87.38μmol/L(R^(2)=0.9946).The limit of detection(LOD)was 0.18μmol/L,which was acceptable compared with the maximum Cr(Ⅵ)concentration of 0.96μmol/L in drinking water prescribed by WHO.In addition,the N,P-CDs/Cr(Ⅵ)hybrid were also used as"turn-on"fluorescent transducers for detecting AA with a wide linear region ranged from 0.02 to933.33μmol/L(R^(2)=0.9972).Furthermore,the N,P-CDs fluorescence sensor had admissible applicability for Cr(Ⅵ)and AA detection in actual water samples with acceptable recovery rate,indicating that the fluorescence sensor had great application potential in environmental monitoring and food field.