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多花黄精多糖提取工艺优化及抗氧化机制研究

合肥工业大学学报（自然科学版） 2024年第5期47卷 678-684页

作者：郭安君李雪影李晓炜罗建平查学强合肥工业大学食品与生物工程学院安徽合肥230601

文章以料液比、提取温度、提取时间为参数,在单因素试验的基础上,采用响应面法优化多花黄精多糖(Polygonatum cyrtonema Hua polysaccharides,PCP)的提取工艺,并分离纯化得到水洗糖;采用氧化低密度脂蛋白(oxidized low-density lipoprot... 详细信息

文章以料液比、提取温度、提取时间为参数,在单因素试验的基础上,采用响应面法优化多花黄精多糖(Polygonatum cyrtonema Hua polysaccharides,PCP)的提取工艺,并分离纯化得到水洗糖;采用氧化低密度脂蛋白(oxidized low-density lipoprotein,Ox-LDL)诱导巨噬细胞氧化应激为实验模型,研究PCP的抗氧化机制。结果显示,PCP的最佳提取工艺为:料液比1∶25,提取温度85℃,提取时间2.0 h。MTT实验结果表明,PCP对巨噬细胞不具有毒性;与模型组相比,PCP显著提高了巨噬细胞的总抗氧化能力(total antioxidant capacity,T-AOC)和谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)的酶活力,降低了丙二醛(MDA)的量,表明PCP具有较强的抗氧化功能。Western Blot实验结果显示,PCP显著上调了Nrf2的蛋白水平,抑制了Keap1的蛋白表达,提示PCP发挥抗氧化作用可能与调控Keap1/Nrf2信号通路有关。研究结果为PCP的深入开发利用提供了一定的理论基础。

关键词：多花黄精多糖(PCP) 响应面法巨噬细胞氧化应激

Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： Jun zha Huijie zhang School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

Identification of the Hammerstein nonlinear system with noisy output measurements

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Control Theory and Technology 2024年第2期22卷 203-212页

作者： Qiming zha Feng Li Ranran Liu School of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou213001JiangsuChina School of Automobile and Traffic Engineering Jiangsu University of TechnologyChangzhou213001JiangsuChina

In this research, we present a methodology to identify the Hammerstein nonlinear system with noisy output measurements. The Hammerstein system presented is comprised of neural fuzzy model (NFM) as its static nonlinear block and auto-regressive with extra input (ARX) model as its dynamic linear block, and a two-step procedure is accomplished using signal combination. In the first step, in the case of input–output of Gaussian signals, the correlation function-based least squares (CF-LS) technique is utilized to identify the linear block, solving the problem that the intermediate variable connecting nonlinear and linear blocks cannot be measured. In the second step, to improve the identification accuracy of the nonlinear block parameters, an improved particle swarm optimization technique is developed under input–output of random signals. The validity and accuracy of the presented scheme are verified by a numerical simulation and a practical nonlinear process, and the results illustrate that the proposed methodology can identify well the Hammerstein nonlinear system with noisy output measurements.

关键词： Hammerstein nonlinear system Signal combination Auto-regressive with extra input Improved particle swarm optimization

水杨酸对霍山石斛类原球茎细胞生长及多糖合成的影响

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生物工程学报 2009年第7期25卷 1062-1068页

作者：王博潘利华罗建平查学强合肥工业大学生物与食品工程学院合肥230009

本研究考察了水杨酸对霍山石斛类原球茎悬浮培养细胞生长、多糖合成、碳代谢的影响,并研究了细胞生长、多糖合成以及蔗糖消耗的动力学。结果表明,水杨酸对霍山石斛类原球茎细胞生长有轻微的抑制作用,但能够显著改善类原球茎对碳源的利用... 详细信息

本研究考察了水杨酸对霍山石斛类原球茎悬浮培养细胞生长、多糖合成、碳代谢的影响,并研究了细胞生长、多糖合成以及蔗糖消耗的动力学。结果表明,水杨酸对霍山石斛类原球茎细胞生长有轻微的抑制作用,但能够显著改善类原球茎对碳源的利用,提高胞内可溶性糖的含量,从而促进多糖的合成,其中以添加100μmol/L浓度的水杨酸效果最好,培养18d时,多糖产量达到3.129g/L,为对照的1.63倍。建立的培养动力学模型能较好地反映水杨酸调控霍山石斛类原球茎悬浮培养过程中细胞生长、多糖合成和蔗糖消耗特性。

关键词：霍山石斛类原球茎水杨酸多糖动力学

Preparing cyclic polymers at high concentrations via self-folding cyclization technique by adjusting the contents of hydrophilic units in linear precursors

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Chinese Chemical Letters 2024年第2期35卷 283-288页

作者： Hao zha Zuowei Wang Chao Liu Chunyan Hong Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Cyclic polymers are a class of polymers that feature endless topology,and the synthesis of cyclic polymers has attracted the attention of many ***,cyclic polymers were efficiently constructed by self-folding cyclization technique at high *** poly((oligo(ethylene glycol)acrylate)-co-(dodecyl acrylate))(P(OEGA-co-DDA))precursors with different ratios of hydrophilic and hydrophobic moieties were synthesized by reversible addition-fragmentation chain transfer(RAFT)polymerization using a bifunctional chain transfer agent with two anthryl end *** amphiphilic linear precursors underwent the self-folding process to generate polymeric nanoparticles in *** irradiating the aqueous solution of the nanoparticles with 365 nm UV light,cyclic polymers were synthesized successfully via coupling of anthryl *** effects of the ratios of hydrophilic and hydrophobic moieties in linear P(OEGA-co-DDA)copolymers and polymer concentration on the purity of the obtained cyclic polymers were explored in detail via ^(1)H nuclear magnetic resonance(^(1)H NMR),dynamic light scattering(DLS),UV‒visible(vis)analysis,three-detection size exclusion chromatography(TD-SEC)and transmission electron microscopy(TEM).It was found that by adjusting the content of the hydrophilic segments in linear precursors,single chain polymeric nanoparticles(SCPNs)can be generated at high polymer ***,cyclic polymers with high purity can be constructed *** method overcomes the limitation of traditional ring-closure method,which is typically conducted in highly dilute conditions,providing an efficient method for the scalable preparation of cyclic polymers.

关键词： Cyclic polymers Self-folding cyclization technique Single chain polymeric nanoparticles RAFT polymerization Direct visualization

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阴离子交换树脂对米糠植酸的吸附解吸性能

农业机械学报 2011年第5期42卷 160-165页

作者：王琳罗建平查学强张海林潘利华合肥工业大学生物与食品工程学院合肥230009

通过静态和动态试验研究了6种阴离子交换树脂对植酸的吸附与解吸性能。结果表明,D201树脂对植酸的吸附交换作用较好,且在pH值为2.2时吸附能力最强,静态吸附量达到94.54 mg/g,1.5 mol/L的NaOH溶液利于植酸解吸;Freundlich吸附等温方程可... 详细信息

通过静态和动态试验研究了6种阴离子交换树脂对植酸的吸附与解吸性能。结果表明,D201树脂对植酸的吸附交换作用较好,且在pH值为2.2时吸附能力最强,静态吸附量达到94.54 mg/g,1.5 mol/L的NaOH溶液利于植酸解吸;Freundlich吸附等温方程可以较好地描述D201树脂对植酸的等温吸附,表明吸附在常温下进行即可;D201树脂对植酸的吸附过程符合Lagergren一级速率方程,表观吸附速率常数k与植酸起始植酸浓度呈负相关关系,与温度呈正相关关系。在D201树脂对植酸的动态吸附与解吸过程中,层析柱管径、上样液浓度、上样液流速和洗脱剂流速对吸附与解吸效果影响较大。

关键词：植酸脱脂米糠阴离子交换树脂吸附交换解吸动力学

Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm

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Defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting zha Hailu Yuan Zhen Zheng He zhang Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

Efficient synthesis of bottle-brush polymers enabled by selective photoactivation strategy in NIR-induced PET-RAFT polymerization

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Science China Chemistry 2024年第7期67卷 2353-2361页

作者： Hao zha Lin Cheng Zuowei Wang Chao Liu Chunyan Hong Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Bottle-brush polymers possessing densely grafted side chains have special properties that are distinct from linear ***,an efficient method for preparing bottle-brush polymers based on a selective photoactivation strategy in the photoinduced electron/energy transfer reversible addition-fragmentation chain transfer(PET-RAFT)polymerization was developed.A methacrylate monomer 2-(2-(dodecylthiocarbonothioylthio)propionate)ethyl methacrylate(DTPEMA)containing a 2-(dodecylthiocarbonothioylthio)propionate(DTP)unit with a secondary R group was *** the unique selectivity of metal naphthalocyanine photocatalyst zinc 2,11,20,29-tetra-tert-butyl-2,3-naphthalocyanine(ZnTtBNc)toward trithiocarbonate with tertiary R group,the PET-RAFT polymerization of DTPEMA catalyzed by ZnTtBNc was performed under near infrared(NIR)light(λ_(max)=760 nm)irradiation at room temperature,using 4-cyano-4-[(dodecylsulfanylthiocarbonyl)-sulfanyl]pentanoic acid(CDTPA)with a tertiary R group as a chain transfer agent(CTA).Proton nuclear magnetic resonance(1H NMR)and gel permeation chromatography(GPC)results demonstrated that the DTP units in the side chains were inert during the *** grafting poly(methyl acrylate)(PMA)from PDTPEMA via thermal-initiated RAFT polymerization,welldefined P(DTPEMA-g-PMA)bottle-brush polymers could be ***,the film prepared from the bottle-brush polymer exhibited excellent scratch self-healing property due to the interlocking of side chains.

关键词： bottle-brush polymers PET-RAFT polymerization selective photoactivation scratch self-healing

金属离子对霍山石斛类原球茎增殖及植株再生的影响

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园艺学报 2006年第1期33卷 179-181页

作者：查学强罗建平石玮姜绍通合肥工业大学生物与食品工程学院合肥230009

采用单因素浓度试验和正交试验研究了Mg2+、Ca2+、Fe2+、Mn2+和Zn2+离子对液体培养霍山石斛类原球茎增殖的影响。结果表明,5种金属离子对类原球茎增殖影响的主次顺序为Fe2+>Mn2+>Mg2+>Ca2+>Zn2+,促进类原球茎增殖的优化组合为Mg2+1.5 mm... 详细信息

采用单因素浓度试验和正交试验研究了Mg2+、Ca2+、Fe2+、Mn2+和Zn2+离子对液体培养霍山石斛类原球茎增殖的影响。结果表明,5种金属离子对类原球茎增殖影响的主次顺序为Fe2+>Mn2+>Mg2+>Ca2+>Zn2+,促进类原球茎增殖的优化组合为Mg2+1.5 mmol.L-1、Ca2+4.5 mmol.L-1、Fe2+0.1mmol.L-1、Mn2+0.5 mmol.L-1、Zn2+0.06 mmol.L-1。经优化的液体培养基增殖的类原球茎能保持植株再生能力,平均每克类原球茎增殖后可再生植株1 985.2株,是相同时间内对照类原球茎再生植株数的4.2倍。

关键词：霍山石斛类原球茎金属离子液体培养植株再生