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Optimization of Fermentation Medium for Epothilones Production with Sequential Statistical Approach

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Chemical Research in Chinese Universities 2010年第1期26卷 86-91页

作者： MENG Fan-xin LI You-xin GUO Wei-liang LU jia-hui DU lin-na TENG Li-rong College of Life Science Jilin University Changchun 130012 P. R. China

A sequential statistical approach was applied to optimizing the fermentation medium of epothilones（Epos） production by means of a mutant which was obtained by treating polyangium cellulosum ATCC 15384 with nitrite and ultraviolet. The effects of different carbon sources and nitrogen sources on the fermentation medium were tested, and the suitable ones were selected. Then a uniform design was employed to design the experiments. A linear model was developed for identifying the significant components in fermentation medium, while a third degree polynomial model was used for studying the relationship between the concentration of the components in fermentation medium and the yield of Epos（YEPs）. A pattern search method was used for searching the optimum fermentation medium in the test space, which was as follows（g/L）： potassium nitrate 8.00, soybean peptone 17.60, potassium hydrogen phos- phate 1.00, beef extraction 6.46, yeast extraction 1.00, calcium chloride 0.25, sodium chloride 1.00 and ferric chloride 0.02. The optimum fermentation medium was expected to result in a yield of Epos（YEPs） of 2.48 mg/L. The validation experiments with the optimum medium were performed in triplicate and the average yield of Epos was 2.45 mg/L which was 7.78 times higher than that of Epos prepared without optimization.

关键词： Statistical approach Epothilones Uniform design Optimization of fermentation medium

CH_(4) and C0_(2) observations from a melting high mountain glacier,Laohugou Glacier No.12

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Advances in Climate Change Research 2022年第1期13卷 146-155页

作者： Zhi-Heng DU Lei WANG Zhi-Qiang WEI Jing-Feng LIU Peng-lin lin jia-hui lin Yan-Zhao LI Zi-Zhen JIN Ji-Zu CHEN Xiao-Xiang WANG Xiang QIN Cun-De XIAO State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Zhuhai Branch of State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityZhuhai 519087China College of Geography and Environment Science Northwest Normal UniversityLanzhou 730000China Qilian Shan Station of Glaciology and Ecological Environment State Key Laboratory of Cry ospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

With global warming,glaciers in the high mountains of China are retreating ***,few data have been reported on whether greenhouse gases from these glaciers are released into the atmosphere or absorbed by glacial *** this study,we collected meltwater and ice samples from Laohugou Glacier No.12 in western China and measured CH_(4)and CO_(2)*** from the glacier terminus was continually sampled between 3 and 5 August 2020 to measure CH_(4)and CO_(2)*** results demonstrated that meltwater is a source of CH_(4)because the average saturations are over 100%.It could be con eluded that CH_(4)in the atmosphere can be released by glacial ***,the CO_(2)saturations are various,and CO_(2)fluxes exhibit positive(released CO_(2))or negative(absorbed CO_(2))values because the water and atmospheric conditions are *** importantly,the CH_(4)and CO_(2)concentrations were higher in meltwater samples from the glacier terminus than in samples from the surface ice(including an ice core)and a surface *** the meltwater effect from the upper part of the glacier cannot be excluded,we speculated that subglacial drainage systems with an anaerobic environment may represent the CH_(4)source,but it needs to be further investigated in the ***,high mountain glaciers are currently ignored in global carbon budgets,and the increased melting of glaciers with global warming may accelerate the absorption of much more CO_(2)and lead to the release of CH_(4).

关键词： CO_(2) CH_(4) Source and sink:Subglacial drainage systems Laohugou glacier No.12

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu lin He lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai jian hui jia Yu Wang Chun Cheng Yang Qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1) at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1) at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

Selenate-based heterojunction with cobalt-nickel paired site for electrocatalytic oxidation of 5-hydroxymethylfurfural coupling water splitting to produce hydrogen

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Journal of Energy Chemistry 2025年第2期101卷 156-162页

作者： Zhengru Yang jia hui Wangxi Fan Pengcheng Liu Chunyong Zhang Shuang Dong Zhou Yang Department of Chemistry and Chemical Engineering & Jiangsu Key Laboratory of Clean Energy Storage and Conversion Jiangsu University of Technology Engineering Technology and Materials Research Center China Academy of Transportation Sciences School of Chemical Engineering and Materials Changzhou Institute of Technology

It is very appealing that 5-hydroxymethylfurfural（HMF） is electrocatalytical oxidized as 2,5-furandicarboxylic acid（FDCA） linking to non-classical cathodic hydrogen（H2） ***,the electrocatalysts for electrocatalytic HMF oxidative reaction（e-HMFOR） have been facing low Faradaic efficiency（FE） and high water splitting ***,we propose a strategy of the NiSeO3@（CoSeO3）4heterojunction by constructing a Co-Ni paired site,where the Co site is in charge of adsorbing for HMF while the electrons are transferred to the Ni site,thus giving the NiSeO3@（CoSeO3）4heterojunction superior electrocata lytic performances for e-HMFOR and water *** optimizing conditions,the NiSeO3@（CoSeO3）4heterojunction has high conversion of 99.7%,high selectivity of 99.9%,and high FE of 98.4% at 1.3 V,as well as low cell voltage of 1.31 V at 10 mA cm-2in 1 M KOH+0.1 M *** study offers a potential insight for e-HMFOR to high value-added FDCA coupling water splitting to produce H2in an economical manner.

关键词： Co-Ni paired site e-HMFOR FDCA Heterojunction Hydrogen evolution

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie jia-lin Li ling Gong Xiang-Li Zhong Hong-jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Facile synthesis of V-doped CoP nanoparticles as bifunctional electrocatalyst for efficient water splitting

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Journal of Energy Chemistry 2019年第12期28卷 182-187页

作者： Jun-Feng Qin jia-hui lin Tian-Shu Chen Da-Peng Liu Jing-Yi Xie Bao-Yu Guo Lei Wang Yong-Ming Chai Bin Dong State Key Laboratory of Heavy Oil Processing Institute of New EnergyChina University of Petroleum(East China)Qingdao 266580ShandongChina Shandong Key Laboratory of Biochemical Analysis College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongChina

Adjusting the intrinsic activity and conductivity of electrocatalysts may be a crucial way for excellent performance for water ***,the rational design of vanadium element doped cobalt phosphide(V-doped CoP)nanoparticles has been investigated through a facile gaseous phosphorization using cobalt vanadium oxide or hydroxide(Co-V hydr(oxy)oxide)as *** physical characterization shows that the homogeneous dispersion of V element on V-doped CoP nanoparticles have obtained,which may imply the enhanced electrocatalytic activity for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The electrochemical measurements of the prepared V-doped CoP in alkaline electrolyte demonstrate the superior electrocatalytic activity for both HER(overpotential of 235 mV@10 mA cm^-2)and OER(overpotential of 340 mV@10 mA cm^-2).Further,V-doped CoP nanoparticles used as anode and cathode simultaneously in a cell require only 370 mV to achieve a current density of 10 mA cm^-*** outstanding electrocatalytic activity may be ascribed to the improved conductivity and intrinsic activity owing to phosphating and the doping of V *** addition,the long-term stability of V-doped Co P has been ***,metal doping into transition metal-based phosphides may be a promising strategy for the remarkable bifunctional electrocatalyst for water splitting.

关键词： V element Doping Bifunctional Phosphorization Electrocatalyst Water splitting

Super-high bed sintering for iron ores:variation and optimization of bed resistance

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Journal of Iron and Steel Research International 2025年第1期32卷 40-51页

作者： Liang-ping Xu lin Xiong hui-bo Liu Xi-duan Yang Ai-xiang Mao Pei-dun Chen Guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Central Research Institute Baosteel Group Co.Ltd.Shanghai201900China Manufacturing Management Department Guangdong Zhongnan Iron and Steel Co.Ltd.Shaoguan512123GuangdongChina Technology and Development Center Shandong Taishan Iron and Steel Group Co.Ltd.Jinan271100ShandongChina

As the bed depth increases,sintering yield increases,but the productivity *** reveal the reasons for the decrease in productivity and explore targeted solutions,the bed resistance of mixtures,wet zone,and combustion zone was analyzed in the *** results showed that the decreased porosity of mixture resulted in the increased bed resistance by 160.56%when the bed depth increased from 600 to 1000 *** improving porosity of 1%by adding loosening bars with optimized size and distribution,the bed resistance decreased,and the productivity increased by 5%.The increase in bed depth increased the thickness of the wet zone from 120 to 680 mm and the resistance from 1.56 to 8.83 *** using a three-stage intensive mixer and pre-adding water for granulation,the moisture of mixture was reduced by 0.6%,and the sintering productivity increased by 4%.Besides,the high bed resistance is mainly caused by the increase in the thickness of the combustion zone from 31.9 to 132.7 mm,and the bed resistance increased from 0.70 to 5.62 *** bed resistance of the combustion zone at 900 mm was increased by 90.51%compared to 700 *** optimization of the distribution of coke breeze,the thickness of combustion zone at the lower layer decreased from 132.7 to 106.84 mm and permeability improved significantly.

关键词： Super-high bed sintering Bed resistance Permeability Productivity Wet zone Combustion zone

Investigation of edge states variation in valley photonic crystals by modulating the refractive index of domain walls

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Optoelectronics Letters 2025年第3期21卷 160-166页

作者： ZHANG Run ZHONG Xingli lin Zhongxi QIU Weibin SU hui Key Laboratory of Optoelectronic Materials Chemistry and Physics Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices Fujian Institute of Research on the Structure of Matter Chinese Academy of Science University of Chinese Academy of Sciences Chinese Academy of Sciences College of Information Science and Engineering Huaqiao University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics, since the valley degree of freedom was introduced into photonic system. Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated. In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls, and the geometric difference between the dielectric columns of the sublattices. Straight photonic crystal waveguides with three types of domain walls (bearded, zigzag, armchair) are constructed. Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands. Our findings might have significant implications in the field of novel optical devices.

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