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A PKS gene, pks-1, is involved in chaetoglobosin biosynthesis, pigmentation and sporulation in Chaetomium globosum

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Science China(Life Sciences) 2012年第12期55卷 1100-1108页

作者： HU Yang HAO XiaoRan LOU Jing zhang ping PAN Jiao zhu XuDong State Key Program of Microbiology and Department of Microbiology College of Life Sciences Nankai University Tianjin 300071 China

Chaetomium globosum is one of the most common fungi in nature. It is best known for producing chaetoglobosins; however, the molecular basis of chaetoglobosin biosynthesis is poorly understood in this fungus. In this study, we utilized RNA inter- ference （RNAi） to characterize a polyketide synthase gene, pks-1, in C. globosum that is involved in the production of chaeto- globosin A. When pks-1 was knocked down by RNAi, the production of chaetoglobosin A dramatically decreased. Knock-down mutants also displayed a pigment-deficient phenotype. These results suggest that the two polyketides, melanin and chaetoglobosin, are likely to share common biosynthetic steps. Most importantly, we found that pks-I also plays a critical role in sporulation. The silenced mutants ofpks-1 lost the ability to produce spores. We propose that polyketides may modulate cellular development via an unidentified action. We also suggest that C. globosum pks-1 is unique because of its triple role in melanin formation, chaetoglobosin biosynthesis and sporulation. This work may shed light on chaetoglobosin biosynthesis and indicates a relationship between secondary metabolism and fungal morphogenesis.

关键词： polyketide synthase (PKS) melanin chaetoglobosin A Chaetomium globosum

Estimating the optimal vegetation coverage for the dominant tree and shrub species over China's northwest drylands

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Science China Earth Sciences 2024年第5期67卷 1500-1517页

作者： Zhongdian zhang Xiaoxu JIA ping zhu Mingbin HUANG Lidong REN Ming’an SHAO School of Geographic Sciences Xinyang Normal UniversityXinyang 464000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Yellow River Delta Modern Agricultural Engineering Laboratory Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Anthropogenic revegetation is an effective way to control soil erosion and restore degraded ecosystems in China's northwest drylands(NWD).However,excessive vegetation cover expansion has long been known to increase evapotranspiration,leading to reduced local water availability,which can in turn threaten the health and services of restored *** the optimal vegetation coverage(OVC)is critical for balancing the trade-off between plant growth and water consumption in water-stressed areas,yet quantitative assessments over the entire NWD are still *** this study,a modified Biome BioGeochemical Cycles(Biome-BGC)model was used to simulate the long-term(1961–2020)dynamics of actual evapotranspiration(ET_(a)),net primary productivity(NPP),and leaf area index(LAI)for the dominant non-native tree(*** and ***)and shrub(*** and ***)species at 246 meteorological sites over *** modified model incorporated the Richards equation to simulate transient unsaturated water flow in a multilayer soil module,and both soil and eco-physiological parameters required by the model were validated using field-observed ETadata for each *** distributions of OVC(given by the mean maximum LAI,LAI_(max))for the dominant species were determined within three hydrogeomorphic sub-areas(i.e.,the loess hilly-gully sub-area,the windy and sandy sub-area,and the desert sub-area).The modified Biome-BGC model performed well in terms of simulating ET_(a) dynamics for the four plant *** distributions of mean ET_a,NPP,and LAI_(max)generally exhibited patterns similar to mean annual precipitation(MAP).In the loess hilly-gully sub-area(MAP:210 to 710 mm),the OVC respectively ranged from 1.7 to 2.9 and 0.8 to 2.9 for *** and *** the windy and sandy sub-area(MAP:135 to 500 mm),the OVC ranged from 0.3 to 3.3,0.5 to 2.6 and 0.6 to 2.1for ***,*** and ***,*** the desert sub-

关键词： Optimal vegetation coverage Water balance Leaf area index Biome-BGC model Dryland

Discharge and mass transfer characteristics of atmospheric pressure gas-solid two-phase gliding arc

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Plasma Science and Technology 2024年第9期26卷 88-96页

作者： Min zhu Yuchen ping Yinghao zhang Chaohai zhang Shuqun WU Department of Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106People’s Republic of China

In this work,a gas-solid two-phase gliding arc discharge(GS-GAD)reactor was *** arc was formed in the gap between the blade electrodes,and solid powder was deposited on the sieve plate positioned beneath the blade electrodes.A range of experimental parameters,including the inter-electrode spacing,gas flow rate,applied voltage,and the type of the powder,were systematically varied to elucidate the influence of solid powder matter on the dynamics of gliding arc discharge(GAD).The discharge images were captured by ICCD and digital camera to investigate the mass transfer characteristics of GS-GAD,and the electrical parameters,such as the effective values of voltage,current,and discharge power were record to reveal the discharge characteristics of *** results demonstrate that powder undergoes spontaneous movement towards the upper region of the gliding arc due to the influence of electric field *** the discharge voltage,decreasing relative dielectric constant of the powder and reducing the electrode-to-sieve-plate distance all contribute to a greater involvement of powder in the GAD process,subsequently resulting in an enhanced powder concentration within the GAD ***,powder located beneath the gliding arc experiences downward resistance caused by the opposing gas flow and *** gas flow rate notably hampers the powder concentration within the discharge region,and the velocity of powder motion in the upper part of the GAD region is *** the condition of electrode-to-sieve-plate distance of 30 mm,gas flow rate of 1.5 L/min,and peak-to-peak voltage of 31 kV,the best combination of arc gliding and powder spark discharge phenomena can be achieved with the addition of Al_(2)O_(3) powder.

关键词： gliding arc discharge atmospheric pressure plasma multiphase discharge mass transfer

Mathematical model and numerical investigation of the influence of spray drying parameters on granule sizes of mold powder

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Particuology 2024年第2期85卷 280-295页

作者： Fei zhang Youyu Lu Shaoyan zhu Funian Han Guanghua Wen ping Tang Zibing Hou College of Materials Science and Engineering Chongqing UniversityChongqing400044China Guizhou Academy of Testing and Analysis Guizhou Academy of SciencesGuiyang550014China

In this work,the formation mechanism of the droplet-to-granule was investigated in detail based on mold powder manufacturing.A specific mathematical model of two-stage spray drying was established to describe droplet and granule motion,heat and mass transfer,and granule morphology during spray ***,the relationships between spray drying parameters(inlet temperature,atomization pres-sure,slurry mass flow rate)and the properties of the drying tower(temperature and velocity fields)and mold powder granules(temperature,evaporation rates,moisture content,and diameter)were simulated and calculated using ANSYS/Fluent *** ensure that the granule size of mold powder was controlled within the ideal range(0.2-0.6 mm)for producing granules with appropriate mechanical and metallurgical properties,the following optimum spray drying parameters were chosen based on the results of the numerical simulation:inlet temperatures,873 K;slurry atomization pressure,1.8 MPa;slurry mass flow rate,0.05 kg *** these parameters,the slurry mass flow rate has the most significant effect on granule size.

关键词： Mold powder slurry Spray drying parameters Mathematical model Numerical simulation Granule sizes

Yolk-shell FeSe_(2)@CoSe_(2)/FeSe_(2) heterojunction as anode materials for sodium-ion batteries with high rate capability and stability

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Journal of Materials Science & Technology 2024年第5期172卷 185-195页

作者： Liuyang zhang Bicheng zhu Difa Xu Zibao Qian ping Xie Tao Liu Jiaguo Yu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Sodium-ion batteries are promising candidates for large-scale grid storage systems and other *** foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw material costs than lithium-ion *** is still challenging to explore desirable anode *** this study,FeSe_(2)@CoSe_(2)/FeSe_(2),with a yolk-shell structure was prepared by ion exchange and *** FeSe_(2)@CoSe_(2)/FeSe_(2)prepared as anode material for sodiumion batteries exhibits excellent rate capability due to the synergistic effect of bimetallic selenides and the interfacial effect of the ***,it delivers high performance(510 mAh g^(-1)at 0.2 A g^(-1)),superior rate capa-bility(90%retention at 5 A g^(-1)),and good long-time cycling stability(78%capacity retention after 1800 cycles at a high current density of 2 A g^(-1)).The optimized sodiumion full cell with FeSe_(2)@CoSe_(2)/FeSe_(2)as the anode and Na 3 V 2(PO 4)3 as the cathode still demonstrates excellent ***,a ca-pacity of 272 mAh g^(-1)(at 1 A g^(-1))within the operating voltage from 1 to 3.8 V can be *** work illustrates the potential of bimetallic selenides with heterostructures for performance enhancement of sodium-ion batteries.

关键词： Cobalt-iron selenide Heterojunctions Sodium storage Anode material Full battery

RESISTANCE OF METALS TO MICROSTRAIN AND ITS INFLUENTIAL FACTORS

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Acta Metallurgica Sinica(English Letters) 1990年第12期3卷 420-425页

作者： zhang Lining zhu ping ZHOU Jinyin Southeast University,Nanjing,China

The microstraining prior to yield of several common metallic materials has been *** resistances of metals to microstrain and to macroyield are believed to be based on different deformation mechanisms and to be changed in different *** influential factors upon the microstraining,such as heat treatment,prestrain,strain-aging and residual stress together with their mechanisms have been also discussed.

关键词： microstrain dislocation plastic deformation

Carbon coated LaFe_(0.92)Pd_(0.08)O_(3) composites for catalytic transfer hydrogenation:Balance in the ability of substrates adsorption and conversion

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Nano Research 2024年第5期17卷 3724-3732页

作者： Bowen Wang Nan zhang ping Xiao Jian zhang Sónia A.C.Carabineiro Junjiang zhu Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de LisboaLargo da Torre2829-516 CaparicaPortugal

Catalytic transfer hydrogenation(CTH)is a green and efficient pathway for selective hydrogenation of unsaturated aldehydes and ***,managing the abilities of solid catalysts to adsorb substrates and to convert them into desired products is a challenging ***,we report the synthesis of carbon coated LaFe_(0.92)Pd_(0.08)O_(3) composites(LFPO-8@C)for CTH of benzaldehyde(BzH)into benzyl alcohol(BzOH),using isopropanol(IPA)as hydrogen *** coating with carbon improves the ability to adsorb/transfer reactants from solution to active sites,and the doping of Pd2+at Fe3+site strengthens the ability of LaFeO_(3) to convert BzH into BzOH.A balanced point between them(i.e.,abilities to adsorb BzH and to convert BzH into BzOH)is obtained at LFPO-8@C,which exhibits a BzOH formation rate of 3.88 mmol·gcat^(-1)·h^(-1) at 180℃ for 3 h,which is 1.50 and 2.72 times faster than those of LFPO-8 and LaFeO_(3)@C.A reaction mechanism is proposed,in which the acidic sites(e.g.,Fe^(4+),oxygen vacancy)are used for the activation of C=O bond of BzH and O-H bond of IPA,and the basic sites(e.g.,lattice oxygen)for the activation ofα-H(O-H)bond of IPA.

关键词： LaFe_(0.92)Pd_(0.08)O_(3) porous carbon catalytic transfer hydrogenation isopropanol reaction mechanism

Presence of notched QRS on paced electrocardiographs as a predictor of poor response to cardiac resynchronization therapy

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Chinese Medical Journal 2014年第15期127卷 2727-2734页

作者： Wang Jiayu zhang ping Li Xuebin zhu Tiangang Li Hua Wang Long Li Ding Wu Cuncao Gao Ying Tian Yun Guo Jihong Department of Cardiac Electrophysiology People's Hospital PekingUniversity Beijing 100044 China

Background Cardiac resynchronization therapy （CRT） on patients with advanced and refractory heart failure has made remarkable ***,notched QRS （nQRS） is commonly seen on electrocardiographs （ECGs） with bundle branch block morphology and on paced ECGs after implantation of a CRT device,which may reflect the heterogeneity of ventricular myocardial depolarization and electrical *** aim of this study was to determine whether patients with more nQRS myocardial segments on paced ECGs had a worse response to CRT than patients with fewer nQRS myocardial *** We prospectively enrolled 56 patients of CRT with chronic heart failure from People＇s Hospital affiliated to Peking University from January 2007 to October *** on nQRS segments on ECGs before CRT,we allocated them to two groups：fewer nQRS （〈2） myocardial segments （lateral,inferior,anterior segments） group （F-nQRS,G1,n=23） and more nQRS （≥2） myocardial segments group （M-nQRS,G2,n=33）.Then according to nQRS segments on ECGs after CRT,we divided them into two groups similarly：fewer nQRS （〈2） myocardial segments group （G3,n=24） and more nQRS （≥2） myocardial segments group （G4,n=32）.This study was approved by the ethics committee of People＇s *** At 6 months in the baseline-ECG group,there was a greater absolute increase in left ventricular ejection fraction （LVEF） in G2 than in G1 （（11.5±8.9）% vs.（5.5±10.4）%,P=0.023）,with the incidence of nonresponse lower in G2than in G1 （9.1% vs.39.1%,P=0.018）.In the paced-ECG group,the absolute increase in LVEF was less in G4 than in G3 （（6.4±8.8）% vs.（12.5±10.4）%,P=0.024） and the incidence of nonresponse was higher in G4 than in G3 （31.3% vs.8.3%,P=0.039）.Multivariate analysis showed that fewer nQRS （〈2） myocardial segments on paced ECGs （odds ratio 13.920） was a predictor of positive response to *** nQRS ≥2 myocardial segments （lateral,inferior,anterior） on paced ECGs may predict a poor response to CRT.

关键词： cardiac resynchronization therapy electrocardiography notched QRS

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu2+-Neocuproine Coordination Interactions

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Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434页

作者： Xiao-Ming An Yi-ping Wang Tang-Song zhu Chong Xing Xu-Dong Jia Qiu-Hong zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing University State Key Laboratory of Coordination Chemistry Nanjing University

Elastomers with high mechanical toughness can guarantee their durability during service life. Self-healing ability, as well as recyclability, can also extend the life of materials and save the consuming cost of the materials. Many efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time, while it remains a challenge to balance the trade-off between the above properties in one system. Herein we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu2+-neocuproine coordination simultaneously. By introducing the reversible multiple hydrogen bonds and strong coordination bonds, we successfully fabricated an extremely tough and self-healing elastomer. The elastomer can achieve an impressive top-notch toughness of 491 MJ/m3. Furthermore, it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy（152.6kJ/m2）. Benefiting from the combination of dynamic interactions, the material was able to self-repair under 80 ℃ conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Hydrogen bond Metal-ligand coordination Self-healing Ultra-tough elastomer