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一株链霉菌的鉴定及其产格尔德霉素的发酵工艺研究

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生物技术通报 2024年第6期40卷 299-309页

作者：杨鹭袁源方志锴林如江红周剑福建医科大学药学院福州350122 福建省微生物研究所福建省新药(微生物)筛选重点实验室福州350007

【目的】对链霉菌Streptomyce ***18-0592进行菌种鉴定,并对其胞外格尔德霉素产量进行发酵工艺优化,旨在提高产量并降低发酵成本。【方法】通过形态特征、培养特征和生理生化特性,结合16S rDNA序列分析构建系统发育树进行菌种鉴定;采用... 详细信息

【目的】对链霉菌Streptomyce ***18-0592进行菌种鉴定,并对其胞外格尔德霉素产量进行发酵工艺优化,旨在提高产量并降低发酵成本。【方法】通过形态特征、培养特征和生理生化特性,结合16S rDNA序列分析构建系统发育树进行菌种鉴定;采用单因素试验优化培养条件及培养基配方,进一步使用最陡爬坡试验和响应面试验优化培养基配方的含量。【结果】通过对链霉菌FIM18-0592的形态特征、培养特征及生理生化特征进行初步培养观察发现,其在ISP2等培养基上生长较好,气生菌丝旺盛,产黑色素。结合16S rDNA分子鉴定,确定该菌为格尔德霉素链霉菌(Streptomyces geldanamycininus)。通过单因素试验对发酵条件以及培养基配方进行优化,得到最适宜菌株发酵的培养条件为转速140 r/min、装液量12%(体积分数)、接种量7%(体积分数)、培养时间144 h。最佳的碳源、氮源、无机盐分别为葡萄糖、黄豆饼粉和硫酸铵。采用最陡爬坡试验和响应面优化试验确定了其最优的发酵培养基为:葡萄糖10.42%、黄豆饼粉1.68%、硫酸铵0.3%、乳酸0.3%、甘油4%、硫酸镁0.1%、碳酸钙0.4%,在此条件下,格尔德霉素的发酵效价达到2887μg/mL,较原始发酵工艺效价提高了66%。【结论】链霉菌FIM18-0592为格尔德霉素链霉菌,通过对其发酵工艺进行优化显著提高格尔德霉素的产量,为格尔德霉素及其衍生物的开发和利用奠定基础。

关键词：格尔德霉素菌种鉴定发酵优化单因素优化响应面试验形态特征培养特性

A State-Migration Particle Swarm Optimizer for Adaptive Latent Factor Analysis of High-Dimensional and Incomplete Data

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IEEE/CAA Journal of Automatica Sinica 2024年第11期11卷 2220-2235页

作者： Jiufang Chen Kechen Liu Xin Luo Ye Yuan Khaled Sedraoui Yusuf Al-Turki MengChu zhou IEEE the College of Computer Science and Technology Chongqing University of Posts and Telecommunications the Department of Computer Science Columbia University the College of Computer and Information Science Southwest University the Department of Electrical and Computer Engineering Faculty of Engineering and also with K.A.CARE Energy Research and Innovation Center King Abdulaziz University the Center of Research Excellence in Renewable Energy and Power Systems the Department of Electrical and Computer Engineering Faculty of Engineering and also with K.A.CARE Energy Research and Innovation Center King Abdulaziz University the Department of Electrical and Computer Engineering New Jersey Institute of Technology

High-dimensional and incomplete(HDI) matrices are primarily generated in all kinds of big-data-related practical applications. A latent factor analysis(LFA) model is capable of conducting efficient representation learning to an HDI matrix,whose hyper-parameter adaptation can be implemented through a particle swarm optimizer(PSO) to meet scalable ***, conventional PSO is limited by its premature issues,which leads to the accuracy loss of a resultant LFA model. To address this thorny issue, this study merges the information of each particle's state migration into its evolution process following the principle of a generalized momentum method for improving its search ability, thereby building a state-migration particle swarm optimizer(SPSO), whose theoretical convergence is rigorously proved in this study. It is then incorporated into an LFA model for implementing efficient hyper-parameter adaptation without accuracy loss. Experiments on six HDI matrices indicate that an SPSO-incorporated LFA model outperforms state-of-the-art LFA models in terms of prediction accuracy for missing data of an HDI matrix with competitive computational ***, SPSO's use ensures efficient and reliable hyper-parameter adaptation in an LFA model, thus ensuring practicality and accurate representation learning for HDI matrices.

关键词： Data science generalized momentum high-dimensional and incomplete (HDI) data hyper-parameter adaptation latent factor analysis (LFA) particle swarm optimization (PSO)

不同物理约束方案下西北地区夏季降水的未来预估对比

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气候变化研究进展 2024年第4期20卷 403-415页

作者：周天仪江志红李伟孙岑霄南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际联合实验室/气象灾害预报预警与评估协同创新中心南京210044

近年来,各种证据表明我国西北地区降水呈现增加的趋势,在未来变暖背景下,西北地区降水如何变化,成为我国学术界和社会广泛关注的问题。文中采用了两种基于物理关系的约束(优选)方法,即涌现约束和帕累托最优集合方案,选择了显著影响夏季... 详细信息

近年来,各种证据表明我国西北地区降水呈现增加的趋势,在未来变暖背景下,西北地区降水如何变化,成为我国学术界和社会广泛关注的问题。文中采用了两种基于物理关系的约束(优选)方法,即涌现约束和帕累托最优集合方案,选择了显著影响夏季西北地区降水的物理因子热带印度洋海温和东亚副热带200 hPa纬向风,对25个CMIP6模式给出的SSP585情景下21世纪末期夏季西北地区降水进行了不同约束方案的预估及对比。结果表明:相对于1995—2014年,基于CMIP6模式集合平均得到的21世纪末期夏季西北地区平均降水增加23%,未经约束的不确定性范围为-8.4%~61.7%。通过热带印度洋海温(东亚副热带200 hPa纬向风)涌现约束后,21世纪末期夏季西北地区降水增加24%(19%),不确定性范围减小为-8.4%~52%(-9%~45%),不确定性分别降低了15%(21%)。进一步利用三变量(中国西北夏季历史降水、热带印度洋海温、东亚副热带200 hPa纬向风)的帕累托最优集合方案得到21世纪末期夏季西北地区平均降水变化增加28%,范围为8%~44%,降低了近39%的不确定性范围。同时帕累托最优集合表明降水增多的区域主要集中在西北地区中部与西部,最大降水增幅达到60%以上。

关键词： CMIP6 帕累托最优集合方案涌现约束降水

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连翘总黄酮提取工艺优化及抗炎活性研究

湖北农业科学 2024年第5期63卷 156-161页

作者：延永靳颜颜张亦琳程敏周伟商洛学院生物医药与食品工程学院陕西商洛726000 陕西秦岭特色生物资源产业技术研究院陕西商洛726000 陕西香菊药业有限公司陕西商洛726000

通过单因素试验和响应面试验设计,评价浸泡时间、料液比、乙醇浓度、提取温度和提取时间对连翘(Forsythia suspensa)总黄酮提取率的影响,建立数学模型,得出二次回归方程,预测连翘总黄酮提取的最佳工艺条件,并对新工艺提取的连翘总黄酮... 详细信息

通过单因素试验和响应面试验设计,评价浸泡时间、料液比、乙醇浓度、提取温度和提取时间对连翘(Forsythia suspensa)总黄酮提取率的影响,建立数学模型,得出二次回归方程,预测连翘总黄酮提取的最佳工艺条件,并对新工艺提取的连翘总黄酮进行小鼠耳廓急性炎症肿胀抑制效果评价,测试连翘总黄酮提取物的抗炎活性。结果表明,最佳工艺条件为料液比1∶20、浸泡时间30 min、提取温度58℃、乙醇浓度60%、提取时间79 min。经验证,新工艺的平均提取率为14.54%。新工艺提取的连翘总黄酮提取液处理二甲苯急性致炎的小鼠耳廓的肿胀值为(15.61±2.73)mg,低于生理盐水处理后的肿胀值(17.21±2.65)mg,体外抗炎试验表明连翘总黄酮提取物可抑制小白鼠耳廓的炎症肿胀。引入浸泡环节的连翘总黄酮提取工艺具有提取率较高、稳定可靠的特点,新工艺提取的连翘总黄酮具有一定的抗炎效果。

关键词：连翘(Forsythia suspensa) 总黄酮提取工艺抗炎

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智能化技术在电气工程自动化控制中的应用

A semi-implicit three-step method based on SUPG finite element formulation for flow in lid driven cavities with different geometries

中国科技纵横 2024年第13期 49-51页

作者：吴周俨侃湖州市中医院浙江湖州 313000

随着经济社会的迅速发展,电气工程项目日渐增多.然而,若此类项目继续采用传统的设计与控制方式,将难以提高电气系统的运行效率,且易出现各种安全事故.因此,在信息时代,电气工程自动化控制势在必行.本文利用计算机技术、智能化技术等手段... 详细信息

随着经济社会的迅速发展,电气工程项目日渐增多.然而,若此类项目继续采用传统的设计与控制方式,将难以提高电气系统的运行效率,且易出现各种安全事故.因此,在信息时代,电气工程自动化控制势在必行.本文利用计算机技术、智能化技术等手段,建立自动化控制系统,实现集中化监控,以便及时发现电气设备的问题,并实现精准控制.

关键词：电气工程自动化控制智能化技术

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 33-45页

作者： Cheng HUAN Dai zhou yan BAO School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

A numerical algorithm using a bilinear or linear finite element and semi-implicit three-step method is presented for the analysis of incompressible viscous fluid problems. The streamline upwind/Petrov-Galerkin (SUPG) stabilization scheme is used for the formulation of the Navier-Stokes equations. For the spatial discretization, the convection term is treated explicitly, while the viscous term is treated implicitly, and for the temporal discretization, a three-step method is employed. The present method is applied to simulate the lid driven cavity problems with different geometries at low and high Reynolds numbers. The results compared with other numerical experiments are found to be feasible and satisfactory.

关键词： Semi-implicit three-step method Streamline upwind/Petrov-Galerkin (SUPG) finite element method (FEM) Unsteady incompressible flows Lid driven cavity problem

Fabrication of GO-TiO_(2)/(Ca,Y)F_(2):Tm,Yb composites with highefficiency optical driving photocatalytic activity for degradation of organic dyes and bacteriostasis

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Rare Metals 2022年第2期41卷 650-662页

作者： Hua Guo Jun Li Xian-Rui Zou hong-Shui Wang An Kang Huan zhou Ming-Jun Li Xiao-yan Zhao School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Tianjin Juncheng Dentistry Clinic Co.LTD Tianjin 300090China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300000China Institute of Biophysics Hebei University of TechnologyTianjin 300401China

Development of photocatalytic materials able to profit from the whole spectrum of sun for efficient organic pollution removal and bacterial elimination is a fascinating strategy in environmental *** current work,GO-TiO_(2)/(Ca,Y)F_(2):Tm,Yb,a full-spectrum composite photocatalyst,was prepared via hydrothermal processing with TiO_(2)/(Ca,Y)F_(2):Tm,Yb particles deposited on the surface of graphene oxide(GO).The surface properties of GO-TiO_(2)/(Ca,Y)F_(2):Tm,Yb were characterized using various characterization techniques including X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and Brunauer–Emmett–Teller(BET)surface area ***,ultraviolet–visible(UV–Vis)diffuse reflectance spectroscopy,electron spin resonance(ESR)and other methods were used to systematically explore the photocatalytic mechanism of GO enhancement of TiO_(2)/(Ca,Y)F_(2):Tm,*** photocatalytic degradation study,the degradation rate of methyl orange(MO)was improved by 40%when GO was added into the TiO_(2)/(Ca,Y)F_(2):Tm,Yb *** addition,the presence of GO also improves the antibacterial ability of TiO_(2)/(Ca,Y)F_(2):Tm,Yb against Escherichia coli and Staphylococcus *** results reveal high efficacy of GOTiO_(2)/(Ca,Y)F_(2):Tm,Yb under full spectrum light irradiation,in which(Ca,Y)F2:Tm,Yb and TiO2 can improve its utilization of full spectrum sunlight,and GO can enhance adsorption ability of dye and electron–hole pair differentiation ability of TiO_(2)/(Ca,Y)F_(2):Tm,Yb.

关键词： Photocatalysis Graphene oxide Upconversion Adsorption

Zr-doped titanium lithium ion sieve and EP-granulated composite:Superb adsorption and recycling performance

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Particuology 2022年第10期20卷 100-110页

作者： Suyu zhou Xiaojing Guo Xi yan yan Chen Wanzhong Lang The Education Ministry Key Laboratory of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional MaterialsDepartment of Chemistry and Chemical EngineeringShanghai Normal UniversityShanghai 200234China

Lithium ion sieve(LIS)has attracted great attention due to its high adsorption selectivity towards Li+.Herein,a new type of Zr-doped Ti-LIS(HZrTO)was synthesized by a simple calcination *** adsorption capacity increased from 56.3 mgg-1(before doping)to 93.2 mgg-1 after doping in LiOH solution(lithium 1.8gL-1).The adsorption isotherm and adsorption kinetics of HZrTO accord with the Langmuir isotherm and the pseudo-second-order kinetic equation,*** experiments showed that HZrTO has good stability and *** addition,HZrTO was granulated via epoxy resin(E-12),and the obtained granular adsorbent showed good adsorption capacity,excellent stability and high selectivity towards Li+.

关键词： Lithium ion sieve Lithium titanium oxide Zr-doped Granulation

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年轻脉冲星周期-磁场分类及演化

天文学报 2024年第2期65卷 111-120页

作者：余竞王德华孙益洪周云刚贵州师范大学物理与电子科学学院贵阳550025

年轻脉冲星多处于超新星遗迹(Supernova Remnant,SNR)中,其分为转动供能脉冲星(Rotation-powered SNR-PSR)、磁星(Magnetar)和中心致密天体(Central Compact Object,CCO),这3类年轻脉冲星有着不同的自旋周期及磁场强度分布.其中,遗迹磁星(SNR-Magnetar)的平均自旋周期比转动供能遗迹脉冲星大近一个量级,平均磁场强度高近两个量级.同时,中心致密天体比转动供能遗迹脉冲星的平均磁场强度低近两个量级.这3类年轻脉冲星不同的物理性质,可能源于其不同的前身星或不同的超新星爆发过程,也可能源于其中子星诞生后的不同演化过程.此外,转动供能遗迹脉冲星比年轻的转动供能非遗迹脉冲星具有更快的平均自旋周期、更大的平均磁场强度和更短的平均特征年龄.这暗示新诞生的中子星经时间约为10^(5)-10^(6)yr的演化过程,其自旋速度将减小近一半,同时其磁场强度也将衰减近一半.

关键词：脉冲星:普通恒星:中子超新星遗迹