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Depth Distributions of Belowground Production, Biomass and Decomposition in Restored Tallgrass Prairie

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Pedosphere 2019年第4期29卷 457-467页

作者： Adam C.VON HADEN Mathew E.DORNBUSH Environmental Science and Policy Graduate Program University of Wisconsin- Green Bay Green Bay WI 54311 (USA) Great Lakes Bioenergy research center University of Wisconsin-Madison Madison WI 53726 (USA) Department of Natural and Applied Sciences University of Wisconsin- Green Bay Green Bay WI 54311 (USA)

Grasslands store large stocks of soil organic carbon(SOC) in the subsoil, but our knowledge of belowground processes becomes less robust with depth. Vertically explicit SOC models typically assume that the depth distribution of belowground production follows the depth distribution of belowground biomass, but this assumption has not been tested. In addition to the effects of soil temperature and moisture on decomposition, some vertically explicit SOC models implement an intrinsic decrease in belowground decomposition with depth, yet this effect has rarely been observed empirically. We simultaneously measured the depth distributions of belowground biomass, production, and litter decomposition to assess whether belowground biomass depth distributions were suitable predictors of belowground production and whether belowground decomposition decreased with soil profile depth. We found that live and total(live +dead) belowground biomass was distributed relatively more shallowly than total belowground production, and thus total belowground biomass was a biased predictor of the vertical distribution of belowground production. The depth distribution of live roots < 2 mm in diameter was found to be the best predictor of total belowground production depth distribution. Using an intact decay core method,we found that belowground litter decomposition decreased by 49% from 0–10 to 30–40 cm depth, and model-simulated effects of soil temperature and moisture accounted for only 9% of the observed decrease with depth. Vertically explicit SOC models can be improved with more accurate empirical belowground production depth distribution estimates, but depth-specific decomposition rates currently implemented in SOC models are necessary to explain observed decreases in belowground litter decay with depth.

关键词： carbon decomposition litter decay model simulation roots soil organic carbon soil organic matter temperate grassland vertical rooting distributions

Crystal Structure,Stability and Dissolution of a Drug-drug Molecular Salt Hydrate of Berberine with Protocatechuic Acid

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Chinese Journal of Structural Chemistry 2018年第3期37卷 400-406页

作者：张燕杰娄本勇黄雅丽张梅林棋 Department of Chemical Engineering and Materials Ocean CollegeMinjiang University Engineering research center of green Dyeing and Finishing in Fujian Provincial University

A drug-drug molecular salt hydrate of berberine and protocatechuic acid has been *** acid lost its carboxylic proton and turned to be protocatechuic anion to form a 1：1：1 organic salt hydrate with berberine,[C（20）H（18）NO4]＋[C7H5O4]^-·H2O（1）.Compound1 crystallizes in the triclinic system,space group P1 with a = 7.9849（5）,b =10.5437（5）,c = 14.3621（5）？,α = 77.983（4）,β = 82.900（4）,γ = 78.024（4）o,V = 1152.82（10） A^3,Mr= 507.48,Dc= 1.462 g/cm^3,μ = 0.929 mm^-1,F（000） = 532,Z = 2,the final R = 0.0488 and w R = 0.1322 for 3993 reflectionswith I 〉 2σ（I）.The hydrate exhibited good solid state stability against humidity,which may result from strong hydrogen-bonding interactions between water molecules and carboxylate *** hydrate also exhibited acceptable solubility and dissolution rate.

关键词： berberine protocatechuic acid molecular salt hydrate non-hygroscopic

Privileged strategies for direct transformations of inert aliphatic C–H bonds

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National Science Review 2014年第2期1卷 172-175页

作者： Guihua Chen Zhang-Jie Shi College of Chemistry and green Chemistry center Peking University

Functional group transformations are central to organic ***,the functionalities used in such transformations are highly active organic groups such as halogens,ester groups and hydroxyl ***–hydrogen bonds are ubiquitous structural motifs in organic compounds,but they are not considered to be functionalgroups because(1)in general,the bond dissociation energy of a C–H bond is high,and therefore,such bonds

关键词： H bonds Privileged strategies for direct transformations of inert aliphatic C

Synthesis and antiviral bioactivity of novel chalcone derivatives containing purine moiety

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Chinese Chemical Letters 2018年第1期29卷 127-130页

作者： Yan-Jiao Wang Da-Gui Zhou Fang-Cheng He Ji-Xiang Chen Yong-Zhong Chen Xiu-Hai Gan De-Yu Hu Bao-An Song State Key Laboratory Breeding Base of green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of Education Research and Development Center for Fine Chemicals Guizhou University

A series of novel chalcone derivatives containing purine moiety was designed and synthesized, and their antiviral activities against cucumber mosaic virus （CMV） and tobacco mosaic virus （TMV） were evaluated in vivo. Bioactivity assays indicated that some compounds showed good antiviral activities against CMV and TMV. It is worth mentioning that compounds 30, 3s, 3w, and 3x exhibited excellent curative activity against CMV, with ECso values of 301.1 μg/mL, 315.7 μg/mL, 282.3 μg/mL, 230.5 μg/mL, respectively, which were better than that of Dufulin （373.7 μg/mL） and Ribavirin （726.3 μg/mL）. In addition, the fluorescence spectroscopy experiment results showed that compound 3o showed strong combining capacity to tobacco mosaic virus coat orotein.

关键词： Chalcone derivatives6-Chloro-purineAntiviral activityCucumber mosaic virusTobacco mosaic virusInteraction mechanisms

Electrocatalytic water splitting:Mechanism and electrocatalyst design

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Nano research 2023年第7期16卷 9142-9157页

作者： Han Wu Qiaoxian Huang Yuanyuan Shi Jiangwei Chang Siyu Lu green Catalysis center College of ChemistryZhengzhou UniversityZhengzhou 450001China

Hydrogen energy,a new type of clean and efficient energy,has assumed precedence in decarbonizing and building a sustainable carbon-neutral ***,hydrogen production from water splitting has seen considerable advancements owing to its advantages such as zero carbon emissions,safety,and high product *** overcome the large energy barrier and high cost of water splitting,numerous efficient electrocatalysts have been designed and ***,various difficulties in promoting the industrialization of electrocatalytic water splitting ***,as high-performance electrocatalysts that satisfy industrial requirements are urgently needed,a better understanding of water-splitting systems is *** this paper,the latest progress in water electrolysis is reviewed,and experimental evidence from in situ/operando spectroscopic surveys and computational analyses is summarized to present a mechanistic understanding of hydrogen and oxygen evolution ***,some promising strategies,including alloying,morphological engineering,interface construction,defect engineering,and strain engineering for designing and synthesizing electrocatalysts are *** believe that this review will provide a knowledge-guided design in fundamental science and further inspire technical engineering developments for constructing efficient electrocatalysts for water splitting.

关键词： water splitting mechanism operando spectroscopy design strategy

Calcium regulation of nucleocytoplasmic transport

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Protein & Cell 2011年第4期2卷 291-302页

作者： Ashapurna Sarma Weidong Yang Department of Biological Sciences Center for Photochemical SciencesBowling Green State UniversityBowling GreenOH 43403USA

Bidirectional trafficking of macromolecules between the cytoplasm and the nucleus is mediated by the nuclear pore complexes(NPCs)embedded in the nuclear envelope(NE)of eukaryotic *** NPC functions as the sole pathway to allow for the passive diffusion of small molecules and the facilitated translocation of larger *** shows that these two transport modes and the conformation of NPC can be regulated by calcium stored in the lumen of nuclear envelope and endoplasmic ***,the mechanism of calcium regulation remains poorly *** this review,we integrate data on the observations of calciumregulated structure and function of the NPC over the past ***,we highlight challenges in the measurements of dynamic conformational changes and transient transport kinetics in the ***,an innovative imaging approach,single-molecule superresolution fluorescence microscopy,is introduced and expected to provide more insights into the mechanism of calcium-regulated nucleocytoplasmic transport.

关键词： nuclear envelope nuclear pore complex nucleocytoplasmic transport calcium stores single-molecule fluorescence microscopy

Synthesis of a novel magnetic biomass-MOF composite for the efficient removal of phosphates:Adsorption mechanism and characterization study

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Chinese Journal of Chemical Engineering 2023年第10期62卷 202-216页

作者： Aaron Albert Aryee Chenping Gao Runping Han Lingbo Qu College of Chemistry Green Catalysis CenterZhengzhou UniversityZhengzhou 450001China

The adverse effects of eutrophication have prompted the use of various remediation techniques for phosphate(PO_(4)^(3-))removal owing to it being the major causative ***,the influence of different solvents and ratios of 2-aminoterepthalicacid on the efficiency of magnetic biomass metal-organic framework composites based on the in situ growth of NH_(2)-MIL-101(Fe)onto magnetized peanut husks towards PO_(4)^(3-)removal was assessed via the adsorption *** magnetic biocomposite labelled as MPN@NH2-MIL-101(Fe)exhibited the best efficiency owing to its mesoporous structures and presence of abundant oxygen and nitrogen possessing functional *** results confirmed MPN@NH2-MIL-101(Fe)to have a high adsorption capacity of(14.0±0.3)mg·L^(-1)at a PO43-concentration of 20 mg·L^(-1)with an associated high stability within pH *** adsorption kinetics for the process was well described by both Elovich and pseudo-second-order kinetic models and was mediated by both internal diffusion and liquid film *** Temkin and Freundlich models fitted the equilibrium data well signifying occurrence of both physical and chemical adsorption on a heterogeneous *** is concluded that MPN@NH2-MIL-101(Fe)is a promising adsorbent for the effective removal of phosphate from a water body.

关键词： Magnetic biomass-MOF composite Adsorption Phosphate Mechanism

N-doped carbon dots coupled NiFe-LDH hybrids for robust electrocatalytic alkaline water and seawater oxidation

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Nano research 2022年第8期15卷 7063-7070页

作者： Peng Ding Haoqiang Song Jiangwei Chang Siyu Lu green Catalysis center and College of ChemistryZhengzhou UniversityZhengzhou 450000China

Electrolysis of seawater offers a highly promising and sustainable route to attain carbon-neutral hydrogen energy without demanding on high-purity water ***,it is severely limited by the undesirable chlorine oxidation reaction(ClOR)on the anode and the releasing toxic chlorine species,inducing anode corrosion and multiple pollutions to reduce the efficiency and sustainability of this *** effective way is to limit the overpotential of oxygen evolution reaction(OER)below 480 mV and thus suppress the ***,we demonstrate that nitrogen-doped carbon dots strongly coupled NiFe layered double hydroxide nanosheet arrays on Ni foam(N-CDs/NiFe-LDH/NF)can efficiently facilitate OER with an ultralow overpotential of 260 mV to deliver the geometric current density of 100 mA·cm^(−2)and a Tafel slope of as low as 43.4 mV·dec−1 in 1.0 M *** importantly,the N-CDs/NiFe-LDH/NF electrode at 100 mA·cm^(−2)shows overpotentials of 285 and 273 mV,respectively,by utilizing 1.0 M KOH with 0.5 M NaCl and 1.0 M KOH with 1.0 M NaCl as the simulated seawater,well avoid triggering ***,despite the complex environment of real seawater,N-CDs/NiFe-LDH/NF still effectively promotes alkaline seawater(1.0 M KOH+seawater)electrolysis with a lifetime longer than 50 and 20 h,respectively,in 1.0 M KOH and alkaline seawater *** investigation result reveals that M–N–C bonding generated between N-CDs and NiFe-LDH intrinsically optimizes the charge transfer efficiency,further promoting the OER kinetics.

关键词： N-doped carbon dots electrocatalysis oxygen evolution reaction(OER) seawater oxidation chlorine oxidation reaction(ClOR)

Nanometer-size Na cluster formation in micropore of hard carbon as origin of higher-capacity Na-ion battery

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npj Computational Materials 2021年第1期7卷 440-447页

作者： Yong Youn Bo Gao Azusa Kamiyama Kei Kubota Shinichi Komaba Yoshitaka Tateyama center for green research on Energy and Environmental Materials(green)and International center for Materials Nanoarchitectonics(MANA) National Institute for Materials Science(NIMS)IbarakiJapan Department of Applied Chemistry Tokyo University of ScienceTokyoJapan Elements Strategy Initiative for Catalysts and Batteries(ESICB) Kyoto UniversityKyotoJapan

Development of high-energy-density anode is crucial for practical application of Na-ion battery as a post Li-ion *** carbon(HC),though a promising anode candidate,still has bottlenecks of insufficient capacity and unclear microscopic *** of the micropore has been recently discussed,however,the underlying sodiation mechanism is still *** we examined the origin for the high-capacity sodiation of HC,based on density functional theory *** demonstrated that nanometersize Na cluster with 3–6 layers is energetically stable between two sheets of graphene,a model micropore,in addition to the adsorption and intercalation *** finding well explains the extended capacity over typical 300 mAhg^(−1),up to 478 mAhg^(−1) recently found in the MgO-templated *** also clarified that the MgO-template can produce suitable nanometersize micropores with slightly defective graphitic domains in *** present study considerably promotes the atomistic theory of sodiation mechanism and complicated HC science.

关键词： battery cluster size