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Journal of Bioresources and Bioproducts 2021年第1期6卷 39-44页

作者： Jingwen Shao Yong ni Lifeng yan CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the Microscaleand Department of Chemical PhysicsiCHEMUniversity of Science and Technology of ChinaHefei 230026China

Furfural is an alternative feedstock and has been used for the production of maleic acid(MA)and fumaric acid(FA)by an oxidation *** eutectic solvents(DESs)were used as the green solvents while sodium chlorate was used as an oxidant and vanadium pentoxide was used as the catalyst at 70-90°C under atmospheric *** was found that several acidic DESs are valid,such as acetic acid/choline chloride(AA/ChCl)and propionic acid/choline chloride(PA/ChCl),and AA/ChCl DES was selected as the solvent for the *** optimal DES is AA/ChCl,and the effect of the amount of oxidant,time,and temperature on the yield of the MA and FA has been systematically studied,and the conversion of furfural can reach 100%while the yield of the MA and FA reached 66.5%under reaction temperature of 80℃ for 12 h,which provides a new green route to synthesis valuable monomers from furfural.

关键词： Furfural Maleic acid Fumaric acid Deep eutectic solvent(des) Oxidation

Determinantal Expressions and Recursive Relations for the Bessel Zeta Function and for a Sequence Originating from a Series Expansion of the Power of Modified Bessel Function of the First Kind

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Computer Modeling in Engineering & Sciences 2021年第10期129卷 409-423页

作者： yan Hong Bai-ni Guo Feng Qi College of Mathematics and Physics Inner Mongolia University for NationalitiesTongliao028043China School of Mathematics and Informatics Henan Polytechnic UniversityJiaozuo454003China School of Mathematical Sciences Tiangong UniversityTianjin300387China

In the paper,by virtue of a general formula for any derivative of the ratio of two differentiable functions,with the aid of a recursive property of the Hessenberg determinants,the authors establish determinantal expressions and recursive relations for the Bessel zeta function and for a sequence originating from a series expansion of the power of modified Bessel function of the first kind.

关键词： Determinantal representation recursive relation series expansion first kind modified Bessel function Bessel zeta function Pochhammer symbol gamma function Hessenberg determinant

Biological control of aflatoxin contamination of crops

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第10期9卷 787-792页

作者： yan-ni YIN Lei-yan yan Jin-hua JIANG Zhong-hua MA Institute of Biotechnology Zhejiang University Hangzhou 310029 China

Aflatoxins produced primarily by two closely related fungi, Aspergillus flavus and Aspergillus parasiticus, are mutagenic and carcinogenic in animals and humans. Of many approaches investigated to manage aflatoxin contamination, bio-logical control method has shown great promise. Numerous organisms, including bacteria, yeasts and nontoxigenic fungal strains of A. flavus and A. parasiticus, have been tested for their ability in controlling aflatoxin contamination. Great successes in reducing aflatoxin contamination have been achieved by application of nontoxigenic strains of A. flavus and A. parasiticus in fields of cotton, peanut, maize and pistachio. The nontoxigenic strains applied to soil occupy the same niches as the natural occurring toxigenic strains. They, therefore, are capable of competing and displacing toxigenic strains. In this paper, we review recent development in biological control of aflatoxin contamination.

关键词： Aflatoxin Aspergillus Biocontrol Food safety

Boundary Regularity for k-Hessian Equations

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Acta Mathematica Sinica,English Series 2023年第12期39卷 2393-2413页

作者： You LI Meng ni LI yan Nan LIU School of Mathematics and Computational Sciences Xiangtan UniversityHunan 411105P.R.China School of Mathematics Southeast UniversityNanjing 211189P.R.China School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048P.R.China

In this paper we focus on the boundary regularity for a class of k-Hessian equations which can be degenerate and(or)singular on the boundary of the *** by the case of Monge-Ampere equations,we first construct sub-solutions,then apply the characteristic of the global Holder continuity for convex functions,and finally use the maximum principle to obtain the boundary Holder continuity for the solutions of the k-Hessian ***,finding such sub-solutions is very difficult due to the complexity of the k-Hessian *** particular,we employ the symmetric mean to overcome the difficulties.

关键词： Dirichlet problem k-Hessian equation symmetric mean

Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro

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World Journal of Stem Cells 2024年第2期16卷 163-175页

作者： yan Ren yan-ni Cui Hong-Wei Wang The Second Clinical Medical College Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology The Second Hospital of Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology Key Laboratory of Molecular Diagnosis and Treatment of Blood Diseases in Shanxi ProvinceTaiyuan 030001Shanxi ProvinceChina

BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital ***(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet *** a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and ***,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or *** propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of *** To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and *** CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental *** cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured ***-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant ***-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead *** Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all Pnificantly

关键词： Hematopoietic stem cells nicotinamide Concentration Proliferation Differentiation Sirtuin 1

Antidepressant effect of Xingnao Jieyu decoction mediated by alleviating neuroinflammation in a rat model of post-stroke depression

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Journal of Traditional Chinese Medicine 2019年第5期39卷 658-666页

作者： yan Yongmei Li Tao Wang dou Zhao Bingbing Zhou Qi Department of Encephalopathy Affiliated hospital of Shaanxi University of Chinese Medicine

OBJECTIVE: To identify the antidepressant effect of Xingnao Jieyu (XNJY) decoction on a post-stroke depression (PSD) rat model and the underlying molecular mechanism. METHODS: We established a rat PSD model by middle cerebral artery occlusion (MCAO) combined with chronic unpredictable mild stress (CUMS). Healthy SD rats were randomly divided into six groups: sham, PSD, fluoxetine (Flu), and XNJY groups at low, middle, and high doses. The sham group underwent sham operation, while the other groups underwent MCAO+CUMS. The Flu and XNJY decoction groups were intragastrically administered with Flu or different doses of XNJY for 21 consecutive days. Histopathological changes in the cortex and hippocampus were observed by staining with hematoxylin and eosin and Terminal-deoxynucleoitidyl Transferase Mediated nick End Labeling. Iba1 positive cells were evaluated by immunofluorescence assay. The expressions of tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), interleukin-1β(IL-1β), 5-hydroxytryptamine (5-HT), and norepinephrine (NE) in the cortex and hippocampus were measured by enzyme linked immunosorbent assay. RESULTS: The PSD group rats had a significant decrease in body weight, consumption of sucrose water, and locomotor activity but an increase in immobility time during a forced swimming test (P nificantly recovered these indices (P nism of the XNJY decoction against PSD. Thus, XNJY might be a promising candidate for the treatment of PSD.

关键词： Depression Stroke Infarction, middle cerebral artery Stress Inflammation Antidepressive agents Xingnao Jieyu

Measurement of HONO flux using the aerodynamic gradient method over an agricultural field in the Huaihe River Basin,China

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Journal of Environmental Sciences 2022年第4期34卷 297-307页

作者： Fanhao Meng Min Qin Wu Fang Jun Duan Ke Tang Helu Zhang dou Shao Zhitang Liao yan Feng Yong Huang Ting ni Pinhua Xie Jianguo Liu Wenqing Liu Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Anhui Institute of Meteorological Sciences Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote SensingHefei 230031China Shouxian National Climatology Observatory Huaihe River Basin Typical Farm Eco-meteorological Experiment Field of China Meteorological AdministrationShouxian 232200China

To investigate nitrous acid(HONO)levels and potential HONO sources above crop rotation *** HONO fluxes were measured by the aerodynamic gradient(AG)method from 14 December 2019 to 2 January 2020 over an agricultural field in the Huaihe River *** ambient HONO levels were measured at two different heights(0.15 and 1.5 m),showing a typical diurnal cycle with low daytime levels and high nighttime *** upward HONO fluxes were mostly observed during the day,whereas deposition dominated at *** diurnal variation of HONO flux followed solar radiation,with a noontime maximum of 0.2 nmol/(m^(2)·sec).The average upward HONO flux of 0.06±0.17 nmol/(m^(2)·sec)indicated that the agricultural field was a net source for atmospheric *** higher HONO/NO_(2)ratio and NO_(2)-to-HONO conversion rate close to the surface suggested that nocturnal HONO was formed and released near the *** unknown HONO source was derived from the daytime HONO budget analysis,with an average strength of 0.31 ppbV/hr at *** surface HONO flux,which was highly correlated with the photolysis frequency J(NO_(2))(R^(2)=0.925)and the product of J(NO_(2))×NO_(2)(R^(2)=0.840),accounted for∼23%of unknown daytime HONO *** significant correlation between HONO fluxes and J(NO_(2))suggests a light-driven HONO formation mechanism responsible for the surface HONO flux during daytime.

关键词： Aerodynamic gradient method HONO flux Huaihe River Basin Agricultural field

Surface-improvement mechanism of hybrid electrochemical discharge process using variable-amplitude pulses

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Chinese Journal of Aeronautics 2020年第10期33卷 2782-2793页

作者： yan ZHANG Zhengyang XU Yu WANG Qin ni Xiang LING School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211800China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics&AstronauticsNanjing 210016China AECC Sichuan Gas Turbine Research Establishment Chengdu 610500China

Superalloys are commonly used in aircraft manufacturing;however,the requirements for high surface quality and machining accuracy make them difficult to *** this study,a hybrid electrochemical discharge process using variable-amplitude pulses is proposed to achieve this *** this method,electrochemical machining(ECM)and electrical discharge machining(EDM)are unified into a single process using a sequence of variable-amplitude pulses such that the machining process realizes both good surface finish and high machining ***,the machining mechanism of the hybrid electrochemical discharge process using variable-amplitude pulses is *** mechanism is investigated by observations of machining waveforms and machined *** is found that,with a high-frequency transformation between high-and low-voltage waveforms within a voltage cycle,the machining mechanism is frequently transformed from EDM to pure *** critical discharge voltage is 40 *** pulse voltages greater than 40 V are applied,the machining accuracy is good;however,the surface has defects such as numerous discharge *** machining accuracy is maintained when high-voltage pulses are replaced by low-voltage pulses to enhance electrochemical *** results indicate that the proposed hybrid electrochemical discharge process using variable-amplitude pulses can yield high-quality surfaces with high machining accuracy.

关键词： Electrical discharge machining Electrochemical machining Hybrid machining Superalloy Variable-amplitude pulse

Shape of slab solidification end under non-uniform cooling and its influence on the central segregation with mechanical soft reduction

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1788-1798页

作者： Jie Li yan-hui Sun Hang-hang An Pei-yuan ni Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgy Northeastern UniversityShenyang 110819China Hesteel Group Technology Research Institute Shijiazhuang 050000China

In order to study the effect of continuous casting process parameters on the shape of slab solidification end under non-uniform cooling,a solidification model of a continuous-cast slab with non-uniform cooling condition was established with ProCAST *** model was verified by the results of nail shooting tests and the infrared temperature measurement *** characteristic parameters were defined to evaluate the uniformity of the shape of slab solidification *** results showed that the nonuniformity at the beginning and end of solidification,the solidification end length,and the solidification unevenness increased with the rise of casting *** each 10°C increase of superheat,the solidification unevenness increased by about ***,the effect of superheat on the solidification end length can be *** secondary cooling strength showed minimal effect on the nonuniformity at the beginning and end of *** the increase in secondary cooling intensity,the solidification end length decreased,but the solidification unevenness *** addition,the central segregation of the slab produced with and without the mechanical soft reduction(MSR)process was *** transverse flow of molten steel with low solid fraction influenced the central segregation morphology under MSR.

关键词： continuous casting heat transfer model nail shooting shape of solidification end central segregation

Carbon nanotubes for flexible batteries: recent progress and future perspective

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National Science Review 2021年第5期8卷 158-174页

作者： Sheng Zhu Jian Sheng Yuan Chen Jiangfeng ni yan Li Beijing National Laboratory for Molecular Sciences Key Laboratory for the Physics and Chemistry of NanodevicesState Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular EngineeringPeking University School of Chemical and Biomolecular Engineering The University of Sydney School of Physical Science and Technology Center for Energy Conversion Materials & Physics(CECMP)Jiangsu Key Laboratory of Thin FilmsSoochow University Light Industry Institute of Electrochemical Power Sources

Flexible batteries, which maintain their functions potently under various mechanical deformations, attract increasing interest due to potential applications in emerging portable and wearable electronics. Significant efforts have been devoted to material synthesis and structural designs to realize the mechanical flexibility of various batteries. Carbon nanotubes(CNTs) have a unique one-dimensional(1 D) nanostructure and are convenient to further assemble into diverse macroscopic structures, such as 1 D fibers, 2 D films and 3 D sponges/aerogels. Due to their outstanding mechanical and electrical properties, CNTs and CNT-based hybrid materials are superior building blocks for different components in flexible batteries. This review summarizes recent progress on the application of CNTs in developing flexible batteries, from closed-system to open-system batteries, with a focus on different structural designs of CNT-based material systems and their roles in various batteries. We also provide perspectives on the challenges and future research directions for realizing practical applications of CNT-based flexible batteries.

关键词： carbon nanotube flexible battery electrochemical energy storage wearable electronics