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Effect of Development Stage on the Artemisinin Content and the Sequence Characterized Amplified Region （SCAR） Marker of High-Artemisinin Yielding Strains of Artemisia annua L.

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Journal of Integrative Plant Biology 2006年第9期48卷 1054-1062页

作者： Long Zhang He-Chun Ye guo-feng li Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Guangdong Key Laboratory of Biotechnology for Plant Development College of Life Sciences South China Normal University Guangzhou 510631 China

The effects of development states on the artemisinin content of clone S1 of Artemisia anuua L. grown in a greenhouse were investigated in the present study. The artemisinin content increased gradually during the phase of vegetative growth and reached its highest level at 8-9 mg/g dry weight （DW） when the S1 was 6 months old on a long day （LD） photoperiod. Treatment with 9-18 d of short day （SD） photoperiod resulted in the artemisinin content reaching and being maintained at a higher level （2.059-2.289 mg/g DW）, twofold that of control plants and plants of S1 presented at the pro-flower budding and flower-budding stages. The artemisinin content varied in different parts of the plant. The artemisinin content of leaves was higher than that of florets and branches. The artemisinin content in middle leaves was higher than that of bottom leaves, and then top leaves. Different densities of capitate glands （the storage organ of artemisinin） located on the surface of leaves, florets, and branches explained the variations in artemisinin content in these parts of the plant. The correlation coefficient between artemisinin content and density of capitate glands on the surface of different organs was 0.987. The genetic marker for artemisinin content was screened using random amplified polymorphic DNA （RAPD） and sequence characterized amplified region （SCAR） techniques. The random primer OPAl5 （5＇-TTCCGAACCC-3＇） could amplify a specific band of approximately 1 000 bp that was present in all high-artemisinin yielding strains, but absent in all low-yielding strains in three independent replications. This specific band was cloned and its sequence was analyzed. This RAPD marker was converted into a SCAR marker to obtain a more stable marker.

关键词： Artemisia annua artemisinin capitate gland random amplified polymorphic DNA (RAPD) sequence characterized amplified region (SCAR)

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纳米银在口腔内科领域中的应用(综述)

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安徽医专学报 2024年第2期23卷 104-106页

作者：马丽琼郭利峰张菁安徽医科大学附属口腔医院(安徽省口腔疾病研究重点实验室) 安徽合肥230032

纳米颗粒广泛应用于生物医学领域的诊断和治疗。在各种金属纳米材料中,纳米银颗粒(AgNPs)具有广谱抗菌和杀菌性能。由于AgNPs具有较大的表面体积比,它可以通过灭活酶和穿透细胞膜的方式杀死微生物,且不产生细菌耐药性。此外,AgNPs毒性低... 详细信息

纳米颗粒广泛应用于生物医学领域的诊断和治疗。在各种金属纳米材料中,纳米银颗粒(AgNPs)具有广谱抗菌和杀菌性能。由于AgNPs具有较大的表面体积比,它可以通过灭活酶和穿透细胞膜的方式杀死微生物,且不产生细菌耐药性。此外,AgNPs毒性低,对生物材料的力学性能没有明显的负面影响。因此,AgNPs已被运用到口腔内科领域,以提高生物材料的抗菌性。该文综述了AgNPs在口腔内科领域的应用,重点介绍了其在抗生物膜形成方面和其对人体细胞的生物相容性方面的研究进展。

关键词：纳米银口腔内科细胞毒性

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Pd cluster decorated free standing flexible cathode for high performance li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： liang guo guoliang Zhang Ruonan Yang Dongmei Zhang Xiuqi Zhang Han Yu Xia li feng Dang Key Laboratory for liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

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Effect of antiallergic herbal agents on chloride channel-3 and immune microenvironment in nasal mucosal epithelia of allergic rhinitis rabbits

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Chinese Medical Journal 2010年第8期123卷 1034-1038页

作者： WANG li-feng XU li-juan guo feng-hua WANG li-na SHEN Xiao-hong Medical College of Nankai University Tianjin 300071 China

Background Allergic rhinitis （AR） is a Th2 dominant cytokine response. Chloride channel-3 （CIC-3） plays an important role in nasal mucosal edema and inflammatory pathologic changes in AR. Antiallergic herbal agents （AHA） are antiallergic herbal products. In the previous study, we have demonstrated that AHA clearly inhibited allergic medium and relieved allergic reaction of AR. The aim of this study was to evaluate the function of CIC-3 and discuss the possible therapeutic effects of AHA on immune microenvironment in AR. Methods AHA were produced and used to treat AR. An animal model of an AR rabbit was established by ovalbumin （OVA）. The rhinitis rabbits were randomly divided into three groups： AHA treated group （AHATG）, model group （MG） and healthy control group （HCG）. The expressions of CIC-3 protein were examined by immunohistochemical method. The mucosal epithelial cells of all the rabbit groups were primarily cultured with tissue culture method in vitro with or without rhlL-4 or rhlL-2. Furthermore, the expressions of CIC-3 mRNA were detected by real-time PCR. The levels of monocyte chemotactic factor-1 （MCP-1） and vascular cell adhesion molecule-1 （VCAM-1） protein in culture supernatants were measured by EliSA. Results The expressions of CIC-3 mRNA increased more in mucosal epithelial cells of MG than those in AHATG and HCG （P 〈0.01）. The levels of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of MG were significantly higher than those in the other two groups （P 〈0.01）. Those were significantly increased in MG untreated 12 hours later than those in other two groups （P 〈0.01）. The expressions of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of MG and HCG treated with rhlL-4 were significantly higher than those in the AHATG treated with rhlL-4 （P 〈0.01）. The levels of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of all groups treated with rhlL-2 showed no significant changes （P 〉0.05）. Conclusions AHA can inhibit the

关键词： chloride channel-3 antiallergic herbal agents allergic rhinitis immune microenvironment

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Dual-additives enable stable electrode-electrolyte interfaces for long life li-SPAN batteries

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Chinese Chemical Letters 2024年第5期35卷 459-465页

作者： Zhenqiang guo Huicong Yang Qian Wei Shengjun Xu Guangjian Hu Shuo Bai feng li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Biochemistry and Molecular Biology College of Life ScienceChina Medical UniversityShenyang 110122China Dalian National Laboratory for Clean Energy Dalian 116023China Shenyang King Power Technology Co. Ltd.Shenyang 110016China

Sulfurized polyacrylonitrile(SPAN)is proposed as a promising cathode material for lithium sulfur ***,the continuous side reactions at the electrolyte-electrode interfaces as well as the slow redox kinetics of SPAN cathode deteriorate the electrochemical *** this study,an electrolyte with dual-additives comprising 2-fluoropyridine(2-FP)and lithium difluorobis(oxalato)phosphate(liDFBOP)was used to improve the performance of li||SPAN cells.2-FP has a lower lowest occupied molecular orbital energy than that of the solvents in the electrolyte,leading to its prior reduction.A liF-rich film can be formed on the electrode,effectively improving the stability of the electrolyte-electrode interfaces and prolonging the ***,liDFBOP could form an electrolyte-electrode interface film containing a large amount of li_(x)PO_(y)F_(z) species,compensating for the kinetic deterioration caused by the lower ionic conductive of liF formed at the electrolyte-electrode ***,an electrode-interface film with good chemical stability and high li^(+) transport was established by liF and li_(x)PO_(y)F_(z)-rich *** li||SPAN cell with the electrolyte containing dual-additives demonstrates an excellent capacity retention of 97.5%after 200 cycles at 1.0 C,25℃,comparing to 56.2%capacity retention without ***,the rate capacities of cells with dual-additives can reach 1128.1 mAh/g at 5 C,comparing to only 813.5 mAh/g using electrolyte without *** results shown that the dual-additives in electrolyte provide a promising strategy for practical application of lithium sulfur batteries with SPAN cathodes.

关键词： Sulfurized polyacrylonitrile lithium metal Interface film 2-Fluoropyridine Difluorobis(oxalato)phosphate

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Experimental investigation on the relevance of mechanical properties and porosity of sandstone after hydrochemical erosion

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Journal of Mountain Science 2016年第11期13卷 2053-2068页

作者： CAI Yan-yan YU Jin FU guo-feng li Hong School of Civil and Hydraulic Engineering Dalian University of Technology Dalian116024 China

Under the effect of chemical etching,the macroscopic mechanical properties,mesoscopic structure,mineral content,and porosity of rocks undergo significant changes,which can lead to the geological disasters; thus,an understanding of changes in the microscopic and macroscopic structure of rocks after chemical etching is *** this study,uniaxial mechanical tests and nuclear magnetic resonance(NMR) spectroscopy were carried out on sandstone samples that had been previously subjected to chemical erosion under different p H *** aim was to study changes in properties and mechanical characteristics,including deformation and strength characteristics,of the rock,and microscopic pore variation characteristics,and to perform preliminary studies of the chemical corrosion *** show that different chemical solutions have a significant influence on the uniaxial compressive strength,the axial strain corresponding to the peak axial stress,elastic modulus,*** the passage of time,porosity increases gradually with exposure to different chemical solutions,and exposure to chemical solutions results in large changes in the NMR T2 curve and T2 spectrum *** exposed to different chemical solutions exhibits different corrosion mechanisms; the root cause is the change of mineral.

关键词： Chemical erosion Hydrochemistry Mechanical properties Nuclear magnetic resonance Porosity Sandstone

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Transient Properties of a Bistable System with Delay Time Driven by Non-Gaussian and Gaussian Noises:Mean First-Passage Time

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Communications in Theoretical Physics 2008年第9期50卷 669-673页

作者： li Dong-Xi XU Wei guo Yong-feng li Gao-Jie Department of Applied Mathematics Northwestern Polytechnical University Xi＇an 710072 China

The mean first-passage time of a bistable system with time-delayed feedback driven by multiplicative non-Gaussian noise and additive Gaussian white noise is investigated. Firstly, the non-Markov process is reduced to the Markov process through a path-integral approach; Secondly, the approximate Fokker-Planck equation is obtained by applying the unified coloured noise approximation, the small time delay approximation and the Novikov Theorem. The functional analysis and simplification are employed to obtain the approximate expressions of MFPT. The effects of non-Gaussian parameter （measures deviation from Gaussian character） r, the delay time τ, the noise correlation time to, the intensities D and a of noise on the MFPT are discussed. It is found that the escape time could be reduced by increasing the delay time τ, the noise correlation time τ0, or by reducing the intensities D and α. As far as we know, this is the first time to consider the effect of delay time on the mean first-passage time in the stochastic dynamical system.

关键词： mean first-passage time delay time non-Gaussian noise Gaussian noise bistable system

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Reduction behavior of hematite in the presence of coke

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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1244-1251页

作者： Ze-hong Wang guo-feng li Yong-sheng Sun Ming-zhao He College of Resources and Civil Engineering Northeastern University Shenyang 110819 China College of Mining Engineering North China University of Science and Technology Tangshan 063009 China CITIC Pacific Mining Management Pty Ltd. 45 St. Georges Terrace Perth WA6000 Australia

The reduction kinetics of hematite in the presence of coke as a reductant was studied via isothermal and non-isothermal thermodynamic analyses. The isothermal reduction of hematite was conducted at a pre-determined temperature ranging from 1423 to 1573 K. The results indicated that a higher reduction temperature led to an increased reduction degree and an increased reduction rate. The non-isothermal reduction of hematite was carried out from room temperature to 1573 K at various heating rates from 5 to 15 K·min^（-1）. A greater heating rate gave a greater reduction rate but decreased reduction degree. With an increase in temperature, both the reduction rate and the reduction degree increased at a smaller rate when the temperature was less than 1150 K, and they increased at a higher rate when the temperature was greater than 1150 K before completion of the reduction reaction. Both the isothermal and the non-isothermal reduction behaviors of hematite were described by the Avrami–Erofeev model. For the isothermal reduction, the apparent activation energy and pre-exponential factor were 171.25 kJ ·mol^（-1） and 1.80 × 10~5 min^（-1）, respectively. In the case of non-isothermal reduction, however, the apparent activation energy and pre-exponential factor were correlated with the heating rate.

关键词： hematite ore reduction reduction kinetics coke

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Construction of MnS/MoS_(2) heterostructure on two-dimensional MoS_(2) surface to regulate the reaction pathways for high-performance li-O_(2) batteries

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Journal of Energy Chemistry 2024年第6期93卷 443-452,I0012页

作者： guoliang Zhang Han Yu Xia li Xiuqi Zhang Chuanxin Hou Shuhui Sun Yong Du Zhanhu guo feng Dang Key Laboratory for liquid-Solid Structure Evolution and.Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061ShandongChina School of Environmental and Material Engineering Yantai UniversityYantai 264005ShandongChina Institute National de la Recherche Scientifique CentreÉnergie Matériaux et TélécommunicationsVarennesQuébec J31S2Canada State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083HunanChina Integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK

The inherent catalytic anisotropy of two-dimensional(2D) materials has limited the enhancement of liO_(2) batteries(LOBs) performance due to the significantly different adsorption energies on 2D and edge *** the adsorption strength in 2D materials to the reaction intermediates is essential for achieving high-performance ***,a MnS/MoS_(2) heterostructure is designed as a cathode catalyst by adjusting the adsorption behavior at the *** from the toroidal-like discharge products on the MoS_(2) cathode,the MnS/MoS_(2) surface displays an improved adsorption energy to reaction species,thereby promoting the growth of the film-like discharge *** can disturb the layer growth of MoS_(2),in which the stack edge plane features a strong interaction with the intermediates and limits the growth of the discharge *** and theoretical results confirm that the MnS/MoS_(2) heterostructure possesses improved electron transfer kinetics at the interface and plays an important role in the adsorption process for reaction species,which finally affects the morphology of li_2O_(2),In consequence,the MnS/MoS_(2) heterostructure exhibits a high specific capacity of 11696.0 mA h g^(-1) and good cycle stability over 1800 h with a fixed specific capacity of 600 mA h g^(-1) at current density of100 mA g^(-1) This work provides a novel interfacial engineering strategy to enhance the performance of LOBs by tuning the adsorption properties of 2D materials.

关键词： li-O_(2)batteries Two-dimensional materials MnS/MoS_(2)heterostructure Edge plane Adsorption behavior

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Acid-base buffer effect of fulvic acid and barium fulvate from weathered coal

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Journal of Coal Science & Engineering(China) 2009年第4期15卷 415-419页

作者： guo Xiao-feng li Xi-feng Mining Engineering Institute Taiyuan University of Science and Technology Taiyuan 030024 China

The acid-base buffer characteristics of fulvic acid (FA) and barium fulvate (BaFA)were analyzed. Each share of the sample or model agents (phthalic acid and salicylic acid)were separately mixed into a series of shares of dilute solutions of HCI or NaOH with a series of concentration. The original pH values of the solutions were arranged from 2 to *** balanced pH of each share was measured. The pH changes show that FA and BaFApossess buffer ability, whereas the model agents do not. The tendency of balanced pHvalues was 5.4 for FA and 7.4 for BaFA, whereas the original pH was 4.0-8.5; balancedpH changed little. At room temperature, the maximum buffer capacities were as follows:18.11 mmol hydroxyl per gram FA, 11.25 mmol hydroxyl per gram BaFA, 1.19 mmol protonper gram FA, and 1.45 mmol proton per gram BaFA. Mathematics analysis shows thatlogarithm of buffer capacities of FA and BaFA is linearly dependent on original pH. Compared with BaFA and model agents, it is concluded that FA buffer capacity against hydroxylrelies not only on its acidic groups, BaFA buffer capacity against hydroxyl does not rely onits acidic groups, and FA buffer capacity against proton is not related with its carboxyl andphenolic hydroxyl group. The pH values of FA-water solutions with different concentrationsfrom 1 to 10 grams per liter were measured. Their pH values were slightly affected by itsconcentration. Thus, FA possesses a much stronger buffer ability against water dilutionthan common buffer agent. All the pH values of FA water solutions were very nearby 5.4,just the same as the balanced pH tendency for adding FA.

关键词： acid-base buffer fulvic acid barium fulvate weathered coal pH value

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