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Advances in Z-scheme semiconductor photocatalysts for the photoelectrochemical applications: A review

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Carbon Energy 2022年第3期4卷 294-331页

作者： Jiaxin Li Hao Yuan Wenjie Zhang Bingjun Jin Qi Feng Jan Huang zhengbo jiao Institute of Materials for Energy and Environment and College of Material Science and EngineeringQingdao UniversityQingdaoP.R.China School of Applied Physics and Materials Wuyi UniversityJiangmenP.R.China

With continuous consumption of nonrenewable energy,solar energy has been predicted to play an essential role in meeting the energy demands and miti gating environmental issues in the future.Despite being green,clean and pollution-free energy,solar energy cannot be adopted directly as it cannot provide sufficiently high energy density to work in the absence of machinery.Thus,it is necessary to develop an effective strategy to convert and store solar energy into chemical energy to achieve social sustainable development using solar energy as the main power source.Photocatalysis,in which semi conductor photocatalysts play a key role,is one of the most promising can didates for realising the effective utilisation of sunlight in a green,low-cost and environmentally friendly method.The photocatalytic efficiency of photo catalysts is considerably influenced by their compositions.Among the various heterostructures,Z-scheme heterojunction is one of the most interesting ar chitecture due to its outstanding performance and excellent artificial imitation of photosynthesis.Z-scheme photocatalysts have attracted considerable at tention in the past few decades.Herein,we review contemporary Z-scheme systems,with a particular focus on mechanistic breakthroughs,and highlight current state-of-the-art systems.Z-type photocatalysts are classified as tradi tional,all-solid-state,direct Z-schemes and S-scheme photocatalysts.The morphology,characterisation and working mechanism of each type of Z-scheme are discussed in detail.Furthermore,the applications of Z-scheme in photoelectrochemical water splitting,nitrogen fixation,pollutant degrada tion and carbon dioxide reduction are illustrated.Finally,we outline the main challenges and potential advances in Z-scheme architectures,as well as their future development directions.

关键词： heterostructure photocatalysis photoelectrochemical water splitting Z-scheme

A pseudoclassical theory for the wavepacket dynamics of the kicked rotor model

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 34-43页

作者： Zhixing Zou jiao Wang Department of Physics and Key Laboratory of Low Dimensional Condensed Matter Physics(Department of Education of Fujian Province) Xiamen UniversityXiamen 361005China Lanzhou Center for Theoretical Physics Lanzhou UniversityLanzhou 730000China

In this study, we propose a generalized pseudoclassical theory for the kicked rotor model in an attempt to discern the footprints of the classical dynamics in the deep quantum regime. Compared with the previous pseudoclassical theory that applies only in the neighborhoods of the lowest two quantum resonances, the proposed theory is applicable in the neighborhoods of all quantum resonances in principle by considering the quantum effect of the free rotation at a quantum resonance. In particular, it is confirmed by simulations that the quantum wavepacket dynamics can be successfully forecasted based on the generalized pseudoclassical dynamics, offering an intriguing example where it is feasible to bridge the dynamics in the deep quantum regime to the classical dynamics. The application of the generalized pseudoclassical theory to the PT-symmetric kicked rotor is also discussed.

关键词： quantum-classical correspondence kicked rotor model pseudoclassical theory wavepacket dynamics

Microbial carbon pump shapes chemical signatures of refractory dissolved organic carbon in ocean water column

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Science China Earth Sciences 2024年第7期67卷 2408-2410页

作者： Ruanhong CAI Nianzhi jiao Fujian Key Laboratory of Marine Carbon Sequestration Xiamen UniversityXiamen 361102China Deparment of Oean Science The Hong Kong Universityof Science and TechnologyHong Kong SAR 999077China Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361102China

The global ocean sequesters a great amount of dissolved organic carbon(DOC),which is mainly originated from indigenous microbial activities(such as photosynthesis and chemoautotrophy)in the water column,as well as various exogenous sources such as riverine input,sediment mobilization,aerosol dissolution,hydrothermal vent effusion,and others(Cai and jiao,2023).

关键词： ocean originated aerosol

Preweaning period is a critical window for rumen microbial regulation of average daily gain in Holstein heifer calves

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Journal of Animal Science and Biotechnology 2024年第1期15卷 396-411页

作者： Shengyang Xu Chong jiao Qiyu Diao Yan Tu Beijing Key Laboratory for Dairy Cow Nutrition Institute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081People’s Republic of China

Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves.

关键词： Average daily gain Calves Preweaning period Rumen microbiota

Microstructural characterization and mechanical properties of(TiC+TiB)/TA15 composites prepared by an in-situ synthesis method

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China Foundry 2024年第2期21卷 168-174页

作者： Zhi-yong Zhang jiao-jiao Cheng Jia-qi Xie Shi-bing Liu Kun Shi Jun Zhao Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China National Key Laboratory of Advanced Casting Technologies Shenyang 110022China

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength,low density,and high modulus.In this study,the TA15-based composites reinforced with a volume fraction of 10% to 25%(TiB+TiC)were prepared using powder metallurgy and casting technique.Microstructural characterization and phase constitution were examined using optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).In addition,the microhardness,room temperature(RT)and high temperature(HT)tensile properties of the composites were evaluated.Results revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and TiC.However,as the volume fraction exceeds 15%,TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like morphology.Microhardness increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%.Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures,but it has an adverse effect on room temperature elongation.Conversely,if the reinforcement volume fraction is below 20%,it can improve high-temperature elongation when the temperature exceeds 600℃.

关键词： titanium matrix composites microstucture microhardness tensile properties in-situ synthesis

Selective immobilization of Pb(Ⅱ)by biogenic whewellite and its mechanism

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Journal of Environmental Sciences 2024年第3期137卷 664-676页

作者： Xingxing Wang Kaiyan Ren Kairui jiao Wenjun Nie Xiaochi An Bin Lian College of Life Sciences College of Marine Science and EngineeringNanjing Normal UniversityNanjing 210023China

The development of bio-adsorbents with highly selective immobilization properties for specific heavy metals is a great challenge,but has important application value.Biogenic whewellite(BW)with high selectivity for Pb(Ⅱ)was synthesized by mineral microbial transformation.The selective immobilization properties and mechanism of BW for Pb(Ⅱ)were analyzed by combining mineral characterization technology and batch adsorption research methods.The results indicated that BW can efficiently and selectively immobilize Pb(Ⅱ)in single or composite heavy metal adsorption solutions,and the immobilized Pb(Ⅱ)is difficult to desorb.BW undergoes monolayer adsorption on Pb(Ⅱ),Qmax≈1073.17 mg/g.The immobilization of Pb(Ⅱ)by BW is a physico-chemical adsorption process with spontaneous heat absorption and an accompanying increase in entropy.In addition,the sequestration of Pb(Ⅱ)by BW remains around 756.99 mg/g even at p H=1.The excellent selective immobilization properties of BW for Pb(Ⅱ)are closely related to its smaller Ksp,electrostatic repulsion effect,organic-inorganic composite structure,acid resistance and the formation of Pb(Ⅱ)oxalate.This study provides beneficial information about the recycling of lead in acidic lead-containing wastewater and composite heavy metal contaminated water bodies.

关键词： Aspergillus niger Biogenic whewellite Pb(Ⅱ) Selective adsorption Immobilization mechanism

A Possible γ-Ray Pulsation from PSR J1740-5340B in the Globular Cluster NGC 6397

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Research in Astronomy and Astrophysics 2024年第1期24卷 285-291页

作者： jiao Zheng Pengfei Zhang Li Zhang Department of Astronomy School of Physics and AstronomyKey Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China

Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a modified radio ephemeris updated by tool tempo2, we analyze the ~15 yr γ-ray data obtained from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detect PSR J1740-5340B's γ-ray pulsation at a confidence level of ~4σ with a weighted H-test value of ~26. By performing a phase-resolved analysis, the γ-ray luminosity in on-pulse interval of PSR J1740-5340B is L_(γ)~ 3.8 × 10^(33) erg s^(-1) using NGC 6397's distance of 2.48 kpc. And γ-rays from the on-pulse part of PSR J1740-5340B contribute ~90% of the total observed γ-ray emissions from NGC 6397. No significant γ-ray pulsation of another MSP J1740-5340A in the GC is detected.Considering that the previous four cases of MSPs in GCs, more data in γ-ray, X-ray, and radio are encouraged to finally confirm the γ-ray emissions from MSP J1740-5340B, especially starving for a precise ephemeris.

关键词： gamma-rays:galaxies (stars:)pulsars:individual(PSR J1740-5340B) (Galaxy:)globular clusters:individual(NGC 6397)

A Provable Positivity-Preserving Local Discontinuous Galerkin Method for the Viscous and Resistive MHD Equations

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Communications on Applied Mathematics and Computation 2024年第1期6卷 279-310页

作者： Mengjiao jiao Yan Jiang Mengping Zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026AnhuiChina

In this paper,we construct a high-order discontinuous Galerkin(DG)method which can preserve the positivity of the density and the pressure for the viscous and resistive magnetohydrodynamics(VRMHD).To control the divergence error in the magnetic field,both the local divergence-free basis and the Godunov source term would be employed for the multi-dimensional VRMHD.Rigorous theoretical analyses are presented for one-dimensional and multi-dimensional DG schemes,respectively,showing that the scheme can maintain the positivity-preserving(PP)property under some CFL conditions when combined with the strong-stability-preserving time discretization.Then,general frameworks are established to construct the PP limiter for arbitrary order of accuracy DG schemes.Numerical tests demonstrate the effectiveness of the proposed schemes.

关键词： Viscous and resistive MHD equations Positivity-preserving Discontinuous Galerkin(DG)method High order accuracy

Carbon efficiency evaluation method for urban energy system with multiple energy complementary

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Global Energy Interconnection 2024年第2期7卷 142-154页

作者： Xianan jiao Jiekang Wu Yunshou Mao Mengxuan Yan School of Automation Guangdong University of TechnologyGuangzhou 510006P.R.China Guangzhou Power Supply Bureau Guangdong Power Grid CompanySouth China Power GridGuangzhou 510660P.R.China School of Electronic Information and Electrical Engineering Huizhou UniversityHuizhou 516007P.R.China

Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources.

关键词： Urban energy systems(UESs) Multiple energy complementary system Carbon efficiency evaluation Data downscaling Subjective and objective weight Gray correlation analysis