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Recalcitrant carbon controls the magnitude of soil organic matter mineralization in temperate forests of northern China

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Forest Ecosystems 2018年第3期5卷 211-220页

作者： Huan Zhang zhiyong zhou Key Laboratory for Fores(Resources &Ecosystem Processes of Beijing Beijing Forestry UniversityBeijing 100083China Institute of Forestry & Ciimate Change Research Beijing Forestry UniversityBeijing 100083China

Background: The large potential of the soil organic carbon(SOC) pool to sequester CO2from the atmosphere could greatly ameliorate the effect of future climate change. However, the quantity of carbon stored in terrestrial soils largely depends upon the magnitude of SOC mineralization. SOC mineralization constitutes an important part of the carbon cycle, and is driven by many biophysical variables, such as temperature and ***: Soil samples of a pine forest, an oak forest, and a pine and oak mixed forest were incubated for 387 days under conditions with six temperature settings(5 °C, 10 °C, 15 °C, 20 °C, 25 °C, 30 °C) and three levels of soil moisture content(SMC, 30%, 60%, 90%). The instantaneous rate of mineralized SOC was periodically and automatically measured using a Li-Cor CO2analyzer. Based on the measured amount of mineralized SOC,carbon fractions were estimated separately via first-order kinetic one-and two-compartment ***: During the 387 day incubation experiment, accumulative mineralized carbon ranged from 22.89 mg carbon(C) ·g-1SOC at 30 °C and 30% SMC for the mixed forest to 109.20 mg C·g-1SOC at 15 °C and 90% SMC for the oak forest. Mineralized recalcitrant carbon varied from 18.48 mg C·g-1SOC at 30 °C and 30% SMC for the mixed forest to 104.98 mg C·g-1SOC at 15 °C and 90% SMC for the oak forest, and contributed at least 80% to total mineralized ***: Based on the results of this experiment, the soil organic matter of the pure broadleaved forest is more vulnerable to soil microbial degradation in northern China; most of the amount of the mineralized SOC derived from the recalcitrant carbon pool. Labile carbon fraction constitutes on average 0.4% of SOC across the three forest types and was rapidly digested by soil microbes in the early incubation stage. SOC mineralization markedly increased with soil moisture content, and correlated parabolically to temperature with the highest value at 15 °C. No significant interacti

关键词： Carbon mineralization Soil carbon fraction Long time incubation Two-compartment model Temperate forest

AN EXTENDED BLOCK RESTRICTED ISOMETRY PROPERTY FOR SPARSE RECOVERY WITH NON-GAUSSIAN NOISE

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Journal of Computational Mathematics 2020年第6期38卷 827-838页

作者： Klara Leffler zhiyong zhou Jun Yu Department of Mathematics and Mathematical Statistics Umea UniversityUmeaSweden. Department of Statistics Zhejiang University City CollegeHangzhou 310015China Department of Mathematics and Mathematical Statistics Umea UniversityUmeaSweden

We study the recovery conditions of weighted mixedl2/lp minimization for block sparse signal reconstruction from compressed measurements when partial block support information is *** show theoretically that the extended block restricted isometry property can ensure robust recovery when the data fidelity constraint is expressed in terms of anlq norm of the residual error,thus establishing a setting wherein we are not restricted to Gaussian measurement *** illustrate the results with a series of numerical experiments.

关键词： Compressed sensing Block sparsity Partial support information Signal reconstruction Convex optimization

Simulation of aggregation effects on co-fired biomass-coal ash in an electrostatic precipitator

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Particuology 2020年第3期18卷 120-126页

作者： Jianyi Lu Zhe Yang Bingyi Xu zhiyong zhou Chenxi Sun MOE Key Laboratory of Resources and Environmental Systems Optimization Beijing 102206China School of Environment Science and Engineering North China Electric Power UniversityBaoding 071003China

Aggregation of fine ash into larger particles benefits fly ash removal in an electrostatic *** aggregation,turbulent aggregation,and electrical aggregation of fine ash (derived from co-firing of biomass fuel and anthracite coal) was simulated under different conditions in an electrostatic precipitator.A population balance model and user-defined function in Fluent were assumed to obtain aggregation kernel functions and calculate the aggregation effects on the co-combusted *** results show that electrical aggregation had an obvious effect on both micron-and submicron-sized *** submicron particles,the effect of thermal aggregation is about ten times greater than turbulent ***,for micron-sized particles,turbulent aggregation is about seven times greater than thermal ***,particle aggregation in the electrostatic precipitator mainly occurs because of electrical aggregation,supplemented by thermal aggregation and turbulent *** the flow velocity is 1.0 m/s,particle volume fraction is 1.4%,and biomass co-firing ratio is 10%,the effects of all three aggregation processes on ash particles are optimized.

关键词： Co-combustion Aggregation Population balance model(PBM) Dust removal Electrostatic precipitator(ESP)

Soil calcium content as the driving factor for vegetative structure and soil microbial function diverging across a fire chronosequence of the boreal forests in northeast China

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Journal of Plant Ecology 2022年第2期15卷 372-384页

作者： zhiyong zhou Ying Shen Bo Wang Huan Zhang Key Laboratory of Forest Ecosystem Process of Beijing Beijing Forestry UniversityBeijing 100083China

The role of biophysical variables in constructing community structure changes with the time since *** major objective of this study is to verify the transition stage and its underlying variables for the postfire forest and soil microbial function in the boreal forested area of China.A 50-year fire chronosequence was presented,and biomass of forbs,shrubs and woody plants was separately weighted to assess their contribution to the whole community with the year since fire(YSF).Simultaneously,soil biophysical properties were measured for stands in different time periods after *** microbial functions,*** efficiency(GE)and carbon use efficiency(CUE),were calculated based on ecoenzymatic and soil nutrient *** terms of vegetative structure,forbs’proportion decreased from 75%to 1.5%,but the proportion of woody plants increased from 0.04%to 70%across this fire *** and CUE of soil microorganisms averaged 0.242 and 0.236 and were significantly higher in 9,15 and 31 YSF than in 2 and 3 *** metal content was significantly increased at the late stage of this fire chronosequence,and soil calcium content showed a positive correlation with woody plant biomass and a negative correlation with soil microbial ***,the present work highlights that the time period of 15 and 31 YSF is a hallmark stage for aboveground vegetative structure and soil microbial function to change in different trends and that the calcium content may partly account for these two divergent trajectories.

关键词： vegetative recovery fire chronosequence soil microbial carbon use efficiency soil ecoenzymatic activity soil microbial biomass soil metal content

Excellent piezoelectric constant and thermal stability in BiScO_(3)-PbTiO_(3) piezoelectric ceramics via domain engineering

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Journal of Materiomics 2022年第2期8卷 319-326页

作者： Yazhu Dong zhiyong zhou Ruihong Liang Xianlin Dong Shanghai Institute of Ceramics Key Laboratory of Inorganic Functional Materials and DevicesChinese Academy of Sciences1295 Dingxi RoadShanghai200050People's Republic of China University of Chinese Academy of Sciences Shijingshan DistrictBeijing100049People's Republic of China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050People's Republic of China

The application of piezoelectric ceramics at high temperature is limited because they can't have both high piezoelectric coefficient and high Curie ***,BiScO_(3)-PbTiO_(3)-based piezoelectric ceramics possessing high Curie temperature and piezoelectric properties simultaneously have drawn increasing attention due to their potential applications at high ***,we reported a novel compositional design of(1-x)[0.36BiScO_(3)-0.64PbTiO_(3)]-xBi(Sn_(1/3)Nb_(2/3))O_(3)(abbreviated as BS-PT-xBSN).BS-PT-xBSN ceramic samples were synthesized by conventional solid state reaction *** to the ternary phase diagram of BS-PT-xBSN ceramics brought up in this work,the morphotropic phase boundaries(MPB)were confirmed,which is located in the vicinity of x¼*** canbe identified that the x=0.02 sample near MPB has the optimal electric performance which are giant piezoelectric coefficient(d_(33)-450 pC/N,higher 18%than undoped samples)and high Curie temperature(T_(c)-368℃)as well as large remant polarization(P_(r)46.6 m C/cm^(2)).In addition,the variation of P_(r) is 3% in the temperature range of 30-180℃ and the depolarization temperature of x=0.02 ceramics is about 280℃.Structural analysis such as in-situ PFM and TEM confirms that giant piezoelectricity and depolarization temperature are attributed to the appearance of nano-domain and complexity of domains as well as the stable domain *** work not only reveal the high potential of BS-PT-xBSN for high-temperature piezo-electric applications but also open up a feasible approach to design new high-temperature piezoelectric ceramics.

关键词： MPB Phase structure Piezoelectric constant Thermal stability

Microstructure Control of Nanoporous Silica Thin Film Prepared by Sol-gel Process

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Journal of Materials Science & Technology 2007年第4期23卷 504-508页

作者： Yiqun XIAO Jun SHEN zhiyong XIE Bin zhou Guangming WU Pohl Institute of Solid State Physics Tongji University Shanghai 200092 China

Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step *** electron microscope （TEM） and particle size analyzer were used to characterize the microstructure and the particle size distribution of the sols. Scanning electron microscopy （SEM）, atomic force microscopy （AFM） and spectroscopic ellipsometer were used to characterize the surface microstructure and the optical properties of the silica films. Stability of the sols during long-term storage was investigated. Moreover,the dispersion relation of the optical constants of the silica films, and the control of the microstructure and properties of the films by changing the catalysis conditions during sol-gel process were also discussed.

关键词： Sol-gel Nanoporous Microstructure Optical constants Silica Thin Film

Studies on ammonium dinitramide and 3,4-diaminofurazan cocrystal for tuning the hygroscopicity

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Chinese Journal of Chemical Engineering 2023年第9期61卷 157-164页

作者： Dongdong Hu Yinglei Wang Chuan Xiao Yifei Hu zhiyong zhou Zhongqi Ren State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Xi’an Modern Chemistry Research Institute Xi’an 710065China China Research and Development Academy of Machinery Equipment Beijing 10089China

Ammonium dinitramide(ADN)is a promising oxidizer with high energy characteristic,which is a relatively new environmentally friendly oxidizer without halogens and carbon ***,ADN has high hygroscopicity when exposed to high humidity air,restricting its applications on the solid *** this paper,a novel energetic cocrystal composed of ammonium dinitramide and 3,4-diaminofurazan(DAF)was proposed and successfully synthesized by antisolvent crystallization method,and the properties of the cocrystal were systematically investigated by analytical characterization and theoretical simulation *** formation of the cocrystal was confirmed by powder X-ray diffraction,differential scanning calorimetry,scanning electron microscopy,infrared spectroscopy and Raman spectroscopy,indicating that the synthesized product was a *** theoretical studies,the ADN/DAF cocrystal structure was predicted,and the powder X-ray diffraction,morphology,water sorption capacity of ADN/DAF cocrystal were calculated,which was consistent with experimental *** results showed that newly prepared cocrystal of ADN/DAF had lower hygroscopicity compared to pure ADN,and the water sorption capacity was reduced from 15.35%to 7.90%.This may be due to the formation of N-H…O medium-strength hydrogen bonds between the ammonium ion of ADN and the O atom of DAF in the cocrystal,which prevents the binding of water molecules in the air and ammonium ions and reduces the probability of ADN binding to water molecules,leading to the reduction of cocrystal *** newly prepared energetic cocrystal can provide theoretical and technical guidance for the study of the anti-hygroscopicity of ADN and advance the practical application of ADN.

关键词： Ammonium dinitramide 3,4-Diaminofurazan Hygroscopicity Cocrystallization Adsorption Kinetics

Adsorption of rubidium ion from aqueous solution by surface ion imprinted materials

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Chinese Journal of Chemical Engineering 2023年第2期54卷 1-10页

作者： Zhongqi Ren Jie Wang Hewei Zhang Fan Zhang Shichao Tian zhiyong zhou State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

A new type of rubidium ion-imprinted polymer has been synthesized by the surface-imprinting technique using methacrylic acid as the functional monomer,the rubidium ion as the template,methanol as the solvent,and silica as a *** glycol dimethacrylate and 2,2-azobisisobutyronitrile were used as acrosslinker and an initiator,*** addition,based on the macrocyclic effect of crown ethers,the 18-crown-6 ligand was introduced as a ligand to fix the template ions *** electron microscopy,zeta-potential analysis,Fourier transform infrared spectroscopy,thermogravimetric analysis,and X-ray photoelectron spectroscopy were performed to characterize the ion-imprinted *** effects of the preparation and adsorption conditions on the adsorption performance of the rubidium ion-imprinted polymer were *** results indicated that the rubidium ion-imprinted polymer has high selectivity and faster kinetics than other adsorbents,with an equilibrium adsorption capacity of 200.19 mg·g^(-1)at 298 K within 25 *** sorption isotherm was well described by the Freundlich isotherm model,while the adsorption kinetics fitted the pseudo-second-order kinetic *** adsorption-desorption experiments showed that the ion-imprinted polymer had good chemical stability and reusability.

关键词： Surface-imprinted material Adsorption Aqueous solution Silica Selectivity

Significantly enhanced piezoelectric performance in Bi_(4)Ti_(3)O_(12)-based high-temperature piezoceramics via oxygen vacancy defects tailoring

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Journal of Materiomics 2021年第1期7卷 59-68页

作者： Xinchun Xie zhiyong zhou Ruihong Liang Xianlin Dong Shanghai Institute of Ceramics Key Laboratory of Inorganic Functional Materials and DevicesChineseAcademy of Sciences1295 Dingxi RoadShanghai200050China University of Chinese Academy of Sciences Shijingshan DistrictBeijing100049China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences19 Yuquan RoadShijinshan DistrictBeijing 100049China

Bismuth titanate (Bi_(4)Ti_(3)O_(12),BIT)piezoelectric materials have attracted increasing attention due to their high-temperature ***,it is quite challenging to simultaneously achieve outstanding piezoelectric properties and high Curie temperature in BIT-based *** this study,oxygen vacancy defects tailoring strategy was utilized to solve this problem,excellent piezoelectric coefficient(32.1 pC/N),and ultrahigh Curie temperature(659℃)are gotten in Bi_(4)Ti_(3)-x(Mn_(1/3)Nb_(2/3))xO_(12)(BTMN)ceramics,which are among the top values in the BIT-based *** importantly,the(Mn_(1/3)Nb_(2/3))(4+d)+complex-ion modified Bi_(4)Ti_(3)O_(12)-based ceramics are characterized with excellent piezoelectric stability up to 500℃(d33>30.0 pC/N at 500℃))and significantly reduced conductivity(only~10^(-7)U-1 cm^(-1)at 500℃).Moreover,enhanced ferroelectricity and good dielectric stability were also *** better comprehensive properties can be ascribed to two ***,the concentration of oxygen vacancy defects is obviously reduced,and their distribution is effectively controlled in BITMN ***,the introduction of(Mn_(1/3)Nb_(2/3))^((4+δ)+)complex-ion gives rise to the antiphase boundaries and massive ferroelectric domain *** works not only reveal the high potential of BITMN ceramics for high-temperature piezoelectric applications but also deepen the understanding of the structure-properties relationship in BIT-based materials.

关键词： Bi_(4)Ti_(3)O_(12) (Mn_(1/3)Nb_(2/3))^((4+δ)+)complex-ion Oxygen vacancy defects Piezoelectricity High-temperature