An Improved Machine Learning Model for Pure Component Property Estimation

Information on the physicochemical properties of chemical species is an important prerequisite when performing tasks such as process design and product design.However,the lack of extensive data and high experimental costs hinder the development of prediction techniques for these properties.Moreover,accuracy and predictive capabilities still limit the scope and applicability of most property estimation methods.This paper proposes a new Gaussian process-based modeling framework that aims to manage a discrete and high-dimensional input space related to molecular structure representation with the group-contribution approach.A warping function is used to map discrete input into a continuous domain in order to adjust the correlation between different compounds.Prior selection techniques,including prior elicitation and prior predictive checking,are also applied during the building procedure to provide the model with more information from previous research findings.The framework is assessed using datasets of varying sizes for 20 pure component properties.For 18 out of the 20 pure component properties,the new models are found to give improved accuracy and predictive power in comparison with other published models,with and without machine learning.

Heteronuclear Magnetisms with Ultracold Spinor Bosonic Gases in Optical Lattices

Motivated by recent realizations of spin-1 NaRb mixtures in the experiments[Phys.Rev.Lett.114,255301(2015);Phys.Rev.Lett.128,223201(2022)],we investigate heteronuclear magnetism in the Mott-insulating regime.Different from the identical mixtures where the boson statistics only admits even parity states from angular momentum composition,for heteronuclear atoms in principle all angular momentum states are allowed,which can give rise to new magnetic phases.While various magnetic phases can be developed over these degenerate spaces,the concrete symmetry breaking phases depend on not only the degree of degeneracy but also the competitions from many-body interactions.We unveil these rich phases using the bosonic dynamical mean-field theory approach.These phases are characterized by various orders,including spontaneous magnetization order,spin magnitude order,singlet pairing order,and nematic order,which may coexist specially in the regime with odd parity.Finally we address the possible parameter regimes for observing these spin-ordered Mott phases.

Establishment and Application of Prevention and Control Techniques of New Sugarcane White Leaf Disease

Aiming at the basic and key technical problems in prevention and control of sugarcane white leaf disease(SCWL),this study systematically overcame key technical bottleneck of prevention and control of new SCWL after 10 years of collaborative research,and achieved several innovative achievements.SCWL phytoplasmas newly recorded in China and the new subgroup of SCWL phytoplasmas(16SrXI-D)were discovered for the first time in Yunnan,and the whole genome analysis of the epidemic subgroup was completed.The main transmission source of SCWL pathogens has been identified as infected seed canes,and Tettigoniella viridis and Clovia conifer were newly discovered as vectors for virus transmission.The disease resistance of 25 main varieties was identified,and 10 control varieties were selected.The prevention and control strategy of"emphasizing early warning,strictly carrying out quarantine,blocking the vectors and controlling residual plants"was put forward,and a comprehensive prevention technique was established through integration of various techniques,and standardized technical regulations were formulated for demonstration application.The promotion and application of these achievements have realized scientific prevention and control of SCWL,effectively curbed the spread of SCWL,and ensured the safety of sugarcane producing areas in China,achieving great economic,social and ecological benefits and providing technical support for high-quality development,loss reduction and efficiency improvement of China's sugar industry.

Recent advances in glycerol valorization via electrooxidation:Catalyst,mechanism and device

Glycerol is one of the most important biomass-based platform molecules,massively produced as a by-product in the biodiesel industry.Its high purification cost from the crude glycerol raw material limits its application and demands new strategies for valorization.Compared to the conventional thermocatalytic strategies,the electrocatalytic strategies can not only enable the selective conversion at mild conditions but also pair up the cathodic reactions for the co-production with higher efficiencies.In this review,we summarize the recent advances of catalyst designs and mechanistic understandings for the electrocatalytic glycerol oxidation(GOR),and aim to provide an overview of the GOR process and the intrinsic structural-activity correlation for inspiring future work in this field.The review is dissected into three sections.We will first introduce the recent efforts of designing more efficient and selective catalysts for GOR,especially toward the production of value-added products.Then,we will summarize the current understandings about the reaction network based on the ex-situ and in-situ spectroscopic studies as well as the theoretical works.Lastly,we will select some representative examples of creating real electrochemical devices for the valorization of glycerol.By summarizing these previous efforts,we will provide our vision of future directions in the field of GOR toward real applications.

Atomically thin α-In2Se3: an emergent two-dimensional room temperature ferroelectric semiconductor

Room temperature ferroelectric thin films are the key element of high-density nonvolatile memories in modern electronics. However, with the further miniaturization of the electronic devices beyond the Moore’s law, conventional ferroelectrics suffer great challenge arising from the critical thickness effect, where the ferroelectricity is unstable if the film thickness is reduced to nanometer or single atomic layer limit. Two-dimensional(2D) materials, thanks to their stable layered structure, saturate interfacial chemistry, weak interlayer couplings, and the benefit of preparing stable ultra-thin film at 2D limit, are promising for exploring 2D ferroelectricity and related device applications. Therefore, it provides an effective approach to overcome the limitation in conventional ferroelectrics with the study of 2D ferroelectricity in van der Waals(vdW) materials. In this review article,we briefly introduce recent progresses on 2D ferroelectricity in layered vdW materials. We will highlight the study on atomically thin α-In2Se3, which is an emergent ferroelectric semiconductor with the coupled in-plane and out-of-plane ferroelectricity. Furthermore, two prototype ferroelectric devices based on ferroelectric α-In2Se3 will also be reviewed.

A review of pulse electrolysis for efficient energy conversion and chemical production

Electrochemical transformation emerges as an important solution to sustainable energy conversion and chemical production.Conventional electrolytic systems usually operate under galvanostatic or potentiostatic conditions that sometimes result in unsatisfactory efficiencies or selectivities.Pulse electrolysis by pulsating and programming the potentials/currents can feature unique tunability to the electrodeelectrolyte interface properties that can give rise to drastically different electrochemical behaviors compared to the steady-state counterparts.Although invented almost 100 years ago,pulse electrolysis has received little attention over the period,but has recently attracted a revived focus toward the energyefficient electrolysis.This review will summarize the history and recent efforts of pulse electrolysis in three categories:water electrolysis,CO_(2)electrolysis and other electrolysis.In each section,the advantage of pulse electrolysis over steady-state electrolysis will be discussed in detail,giving a comprehensive overview of the pulse effect on the electrolytic systems.Finally,we will provide our vision of future directions in pulse electrolysis based on previous works.

Ultrathin origami accordion-like structure of vacancy-rich graphitized carbon nitride for enhancing CO_(2) photoreduction

Retaining the ultrathin structure of two-dimensional materials is very important for stabilizing their catalytic performances.However,aggregation and restacking are unavoidable,to some extent,due to the van der Waals interlayer interaction of two-dimensional materials.Here,we address this challenge by preparing an origami accordion structure of ultrathin twodimensional graphitized carbon nitride(oa-C_(3)N_(4))with rich vacancies.This novel structured oa-C_(3)N_(4) shows exceptional photocatalytic activity for the CO_(2) reduction reaction,which is 8.1 times that of the pristine C_(3)N_(4).The unique structure not only prevents restacking but also increases light harvesting and the density of vacancy defects,which leads to modification of the electronic structure,regulation of the CO_(2) adsorption energy,and a decrease in the energy barrier of the carbon dioxide to carboxylic acid intermediate reaction.This study provides a new avenue for the development of stable highperformance two-dimensional catalytic materials.

Realization of High-Fidelity Controlled-Phase Gates in Extensible Superconducting Qubits Design with a Tunable Coupler

High-fidelity two-qubit gates are essential for the realization of large-scale quantum computation and simulation.Tunable coupler design is used to reduce the problem of parasitic coupling and frequency crowding in manyqubit systems and thus thought to be advantageous. Here we design an extensible 5-qubit system in which center transmon qubit can couple to every four near-neighboring qubits via a capacitive tunable coupler and experimentally demonstrate high-fidelity controlled-phase(CZ) gate by manipulating central qubit and one nearneighboring qubit. Speckle purity benchmarking and cross entropy benchmarking are used to assess the purity fidelity and the fidelity of the CZ gate. The average purity fidelity of the CZ gate is 99.69±0.04% and the average fidelity of the CZ gate is 99.65±0.04%, which means that the control error is about 0.04%. Our work is helpful for resolving many challenges in implementation of large-scale quantum systems.

Dynamics of Quantum State and Effective Hamiltonian with Vector Differential Form of Motion Method

Effective Hamiltonians in periodically driven systems have received widespread attention for realization of novel quantum phases, non-equilibrium phase transition, and Majorana mode. Recently, the study of effective Hamiltonian using various methods has gained great interest. We consider a vector differential equation of motion to derive the effective Hamiltonian for any periodically driven two-level system, and the dynamics of the spin vector are an evolution under the Bloch sphere. Here, we investigate the properties of this equation and show that a sudden change of the effective Hamiltonian is expected. Furthermore, we present several exact relations, whose expressions are independent of the different starting points. Moreover, we deduce the effective Hamiltonian from the high-frequency limit, which approximately equals the results in previous studies. Our results show that the vector differential equation of motion is not affected by a convergence problem, and thus, can be used to numerically investigate the effective models in any periodic modulating system. Finally, we anticipate that the proposed method can be applied to experimental platforms that require time-periodic modulation, such as ultracold atoms and optical lattices.

Ground State and Its Topological Properties of Three-Dimensional Spin-Orbit Coupled Degenerate Fermi Gases

Three-dimensional(3D)degenerate Fermi gases in the presence of spin-orbit coupling,inducing various kinds of physical findings and phenomena,have attracted tremendous attention in these years.We investigate the 3D spin-orbit coupled degenerate Fermi gases in theory and first present the analytic expression of their ground state.Our study provides an innovative perspective into understanding of the topological properties of 3D unconventional superconductors,and describes the topological phase transitions in trivial and topological phase areas.Further,such a system is provided with a richer set of Cooper pairings than traditional superconductors.The dual Cooper pairs with same spin directions emerge and exhibit peculiar behaviors,leading to topological phase transitions.Our study and discussion can be generalized to some other types of unconventional superconductors and areas of optical lattices.

Realization of Fast All-Microwave Controlled-Z Gates with a Tunable Coupler

The development of high-fidelity two-qubit quantum gates is essential for digital quantum computing.Here,we propose and realize an all-microwave parametric controlled-Z(CZ)gates by coupling strength modulation in a superconducting Transmon qubit system with tunable couplers.After optimizing the design of the tunable coupler together with the control pulse numerically,we experimentally realized a 100 ns CZ gate with high fidelity of 99.38%±0.34%and the control error being 0.1%.We note that our CZ gates are not affected by pulse distortion and do not need pulse correction,providing a solution for the real-time pulse generation in a dynamic quantum feedback circuit.With the expectation of utilizing our all-microwave control scheme to reduce the number of control lines through frequency multiplexing in the future,our scheme draws a blueprint for the high-integrable quantum hardware design.

Angular Momentum Josephson Effect between Two Isolated Condensates

We demonstrate that the two degenerate energy levels in spin–orbit coupled trapped Bose gases,coupled by a quenched Zeeman field,can be used for angular momentum Josephson effect.In a static quenched field,we can realize a Josephson oscillation with a period ranging from millisecond to hundreds of milliseconds.Moreover,by a driven Zeeman field,we realize a new Josephson oscillation,in which the population imbalance may have the same expression as the current in the direct-current Josephson effect.When the dynamics of the condensate cannot follow up the modulation frequency,it is in the self-trapping regime.This new dynamic is understood from the time-dependent evolution of the constant-energy trajectory in the phase space.This model has several salient advantages compared to the previous ones.The condensates are isolated from their excitations by a finite gap,thus can greatly suppress the damping effect induced by thermal atoms and Bogoliubov excitations.The oscillation period can be tuned by several orders of magnitude without influencing other parameters.In experiments,the dynamics can be mapped out from spin and momentum spaces,thus it is not limited by the spatial resolution in absorption imaging.This system can serve as a promising platform for matter wave interferometry and quantum metrology.

基于CPFD方法的甲烷无氧芳构化流化床反应器数值模拟

基于计算颗粒流体力学(CPFD)方法对甲烷无氧芳构化催化反应/催化剂再生系统中的流化床反应器进行了数值模拟,并将模拟结果与实验结果进行比较,验证了CPFD模拟的可行性。通过模拟得到了反应器内整体气固流动状态、气相各组分浓度分布及催化剂积碳含量分布等,考察了不同操作条件如甲烷进料流量及反应器内催化剂存留量对气固两相流动及甲烷无氧芳构化反应性能的影响。结果表明,甲烷进料流量增加会降低甲烷转化率,提高芳烃选择性;反应器内催化剂存留量增加会加剧床内气固两相的返混程度,提高甲烷转化率,降低芳烃选择性。

仿DNase酶的双金属分级多孔MOFs:制备与抗细菌生物膜应用

本研究成功构建了具有切割DNA能力的双金属枝状大孔金属有机框架(MOFs;HMUiO-66(Zr/Ce)),并将其用于高效破坏生物膜并抑制细菌生长.通过改变Zr/Ce的投料比,可在0-69%的范围内精确调控Zr/Ce的引入量,并控制其粒径在1μm-150 nm之间.HMUiO-66(Zr/Ce)具有独特的化学和热稳定性,开放的大孔结构和可接近的Lewis酸活性位点,表现出模拟DNA酶活性.双金属MOFs中丰富的Zr-OH位点能有效地捕获核酸,而相邻的Ce-OH基团对磷氧键形成亲核攻击,协同放大DNA的水解速率,使得开发的HMUiO-66(Zr/Ce)能够作为切割细胞外DNA和清除细菌生物膜的纳米药物.在此基础上,我们设计了一种仿生HMUiO-66(Zr/Ce)/PVDF膜,该生物膜可抑制细菌粘附和定植,在抗菌治疗和医疗器械中具有广阔的应用前景.

Charm physics with overlap fermions on 2+1-flavor domain wall fermion configurations

Decay constants of pseudoscalar mesons D,D_(s),η_(c) and vector mesons D^(*),D_(s)^(*),J/ψ are determined from the N_(f)=2+1 lattice QCD at a lattice spacing a~0.08 fm.For vector mesons,the decay constants defined by tensor currents are given in the MS scheme at 2 GeV.The calculation is performed on domain wall fermion configurations generated by the RBC-UKQCD collaborations and the overlap fermion action is used for the valence quarks.Comparing the current results with our previous results at a coarser lattice spacing a ~0.11 fm provides a better understanding of the discretization error.We obtain f_(D_(s)^(*))^(T)(MS,2 GeV)/f_(D_(s)^(*))=0.909(18)with a better precision than our previous result.Combining our f_(D_(s)^(*))=277(11)MeV with the total width of D_(s)^(*) determined in a recent study gives a branching fraction 4.26(52)×10^(-5) for D_(s)^(*) leptonic decay.

Electric-field-controlled highly regioselective thiocyanation of N-containing heterocycles

Achieving highly regioselective synthesis in organic chemistry is challenging due to the uncontrollable orientation between reacting partners.External electric fields(EEFs)can influence the reactivity and selectivity of the substrate by causing directional adsorption.However,scalable and efficient techniques for using EEFs as“smart catalysts”have been lacking,hindering their application.In this study,we present a novel method for modifying the regioselectivity of quinoxaline-2(1H)-ones by functionalizing their C7-position using the electric double layer(EDL)theory.This approach led to moderate to good yields of the corresponding C7-thiocyanation products.DFT calculations and control experiments demonstrated that EEFs could reverse the regioselectivity of quinoxaline-2(1H)-ones,allowing the C7-thiocyanation to proceed via a radical reaction mechanism.Additionally,the resulting 7-thiocyano-1-methylquinoxaline-2(1H)-ones exhibited promising AIE properties.Our work showcases a promising strategy for achieving highly regioselective functionalization by aligning the electric field with the desired reaction/bond axis.

Unlocking the power of ions toward enhanced electrocatalysis

Electrocatalysis plays a vital role in advancing energy conversion and storage technologies.In addition to the prominent strategies of advanced electrocatalysts,the exploration of the ion effects on electrocatalytic processes constitutes an emerging topic.Despite significant progress,challenges persist in understanding the controversial mechanisms and addressing the universality of these ion effects.In this feature article,we summarize our recent advances in exploring the ion effects on electrocatalytic oxidation reactions,mainly involving three systems:(1)hierarchical borate and fluoride anions synergize neutral water oxidation;(2)cation-intermediate interactions steer the glycerol oxidation selectivity;(3)cation coordination delays catechol polymerization and promotes selective ring C–C cleavage.These findings not only enrich our understanding of the ion effects through specific non-covalent interactions but also shed light on the potential of finely-tuned electrode–electrolyte interfaces toward the improved electrocatalytic performance for various electrocatalytic applications.After the summary,we outline the current challenges and opportunities within the ionic effect studies and offer insights into prospective research directions.

Form factor for Dalitz decays from J/ψ to light pseudoscalars

We calculate the form factor M(q^(2))for the Dalitz decay J/ψ→γ*(q^(2))η(N_(f)=1)with η(N_(f))being the SU(N_(f))flavor singlet pseudoscalar meson.The difference among the partial widths Г(J/ψ→γη(N_(f)))at different N_(f) can be attributed in part to the N_(f) and quark mass dependences induced by the U_(A)(1)anomaly dominance.M(q^(2))in both N_(f)=1,2 is well described by the single pole model M(q^(2))=M(0)/(1-q^(2)/Λ^(2)).Combined with the known experimental results of the Dalitz decays J/ψ-Pe^(+)e^(−),the pseudoscalar mass mp dependence of the pole parameter A is approximated byΛ(m^(2)_(p))=Λ_(1)(1-m^(2)_(p)/Λ_(2))withΛ_(1)=2.65(5)GeV andΛ_(2)=2.90(35)GeV.These results provide inputs for future theoretical and experimental studies on the Dalitz decays J/ψ→Pe^(+)e^(−).

一种基于亚磷酸盐及其脱氢酶的植物磷利用和杂草控制系统的建立

磷是植物生长发育所必需的大量营养元素之一。土壤中存在大量的正磷酸盐(Pi),但由于土壤化学和微生物转化使得土壤可利用磷的浓度并不高。土壤缺磷以及杂草的抗除草剂能力已成为当前农业可持续发展的重要限制因素,所以提高植物对土壤磷的吸收利用能力或寻求可替代正磷酸盐的磷肥以及开发新型杂草控制系统已成为亟待解决的问题。自然界中亚磷酸盐(Phi)是含量仅次于正磷酸盐的磷源,但仅在某些细菌中能被专一性的亚磷酸盐脱氢酶(PTDH)氧化利用,对植物的生长发育则具有抑制作用。利用这一特性,将从土壤宏基因组中直接扩增到的假单胞菌PTDH基因PsPtx通过农杆菌侵染法转入烟草中,并通过RT-PCR、垂直板幼苗生长、显性标记和生长竞争实验分析PsPtx转基因烟草的基因表达以及在Phi胁迫条件下的特性。结果显示,PsPtx在其转基因植株的根茎叶组织中都有几乎相同水平的表达;PsPtx转基因烟草不但能解除Phi对植物的毒害作用,并将它氧化成可用的Pi作为生长发育所需的磷源,而且在Phi胁迫条件下较野生型烟草有相当明显的生长竞争优势;另外PsPtx还具备成为植物遗传转化显性选择标记的优良特质。因此,PsPtx基因编码的亚磷酸盐脱氢酶可用于开发一种基于亚磷酸盐为磷肥和除草剂的植物磷利用和杂草控制系统,为当前农作物转基因研究存在的一些重大问题提供一个有效解决方案。

A mini review on nickel-based electrocatalysts for alkaline hydrogen evolution reaction

High gravimetric energy density, earth-abundance, and environmental friendliness of hydrogen sources have inspired the utilization of hydrogen fuel as a clean alternative to fossil fuels. Hydrogen evolution reaction （HER）, a half reaction of water splitting, is crucial to the low-cost production of pure H2 fuels but necessitates the use of electrocatalysts to expedite reaction kinetics. Owing to the availability of low-cost oxygen evolution reaction （OER） catalysts for the counter electrode in alkaline media and the lack of low-cost OER catalysts in acidic media, researchers have focused on developing HER catalysts in alkaline media with high activity and stability. Nickel is well-known as an HER catalyst and continuous efforts have been undertaken to improve Ni-based catalysts as alkaline electrolyzers： In this review, we summarize earlier studies of HER activity and mechanism on Ni surfaces, along with recent progress in the optimization of the Ni-based catalysts using various modern techniques. Recently developed Ni-based HER catalysts are categorized according to their chemical nature, and the advantages as well as limitations of each category are discussed. Among all Ni-based catalysts, Ni-based alloys and Ni-based hetero-structure exhibit the most promising electrocatalytic activity and stability owing to the fine-tuning of their surface adsorption properties via a synergistic nearby element or domain. Finally, selected applications of the developed Ni-based HER catalysts are highlighted, such as water splitting, the chloralkali process, and microbial electrolysis cell.