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Differences in regenerated silk fibroin prepared with different solvent systems: From structures to conformational changes

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Differences in regenerated silk fibroin prepared with differ...

Differences in regenerated silk fibroin prepared with different solvent systems: From structures to conformational changes

第十二届家（柞）蚕遗传育种暨良种繁育学术研讨会

作者： Guotao Cheng Xin Wang sijie tao Ju Xia Shui Xu College of Biotechnology Southwest University

Dissolution is an important part of silk fibroin(SF) reprocessing, and it is the only way to process it into films, gels, porous scaffold materials, and electrostatic spinning silk fibers. There are a variety of dissolution systems used to dissolve SF. However, few studies have focused on the differences between these different solvent systems. The dissolution of SF with different solventsystems was investigated in this study. Regenerated silk fibroin(RSF) solutions and films were characterized by dynamic light scattering, Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. The results show that the RSF film structures changed with the solvent system, especially LiBr–HO. The characterization proved that the random coil did not change into a b-sheet structure during film formation, and this indicated that its crystal structure and thermal stability was different from others. Interestingly, the differences in the morphologies of all of the RSF films prepared with different solvents were outstanding. Because the mechanism and force of the ion in the solvent systems were different, the SF molecule was hydrolyzed differently in individual solvent systems and produced different hydrolyzed SF molecular chains. These chains had different self-assembly processes and would lead to RSF products with different microstructures and properties. This suggests that a suitable solvent should be chosen for different uses.

关键词： biomaterials films properties and characterization

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Differences in regenerated silk fibroin prepared with differ...

面向组织工程应用的再生丝素/海藻酸钙海绵:制备、表征及体内、体外性能研究

第十二届家（柞）蚕遗传育种暨良种繁育学术研讨会

作者： Cheng Guotao Wang Xin tao sijie Xia Ju Xu Shui College of Biotechnology Southwest University

Dissolution is an important part of silk fibroin（SF） reprocessing, and it is the only way to process it into films, gels, porous scaffold materials, and electrostatic spinning silk fibers. There are a variety of dissolution systems used to dissolve SF. However, few studies have focused on the differences between these different solvent systems. The dissolution of SF with different solvent systems was investigated in this study. Regenerated silk fibroin（RSF） solutions and films were characterized by dynamic light scattering, Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. The results show that the RSF film structures changed with the solvent system, especially Li Br–H2O. The characterization proved that the random coil did not change into a b-sheet structure during film formation, and this indicated that its crystal structure and thermal stability was different from others. Interestingly, the differences in the morphologies of all of the RSF films prepared with different solvents were outstanding. Because the mechanism and force of the ion in the solvent systems were different, the SF molecule was hydrolyzed differently in individual solvent systems and produced different hydrolyzed SF molecular chains. These chains had different self-assembly processes and would lead to RSF products with different microstructures and properties. This suggests that a suitable solvent should be chosen for different uses.

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材料导报 2020年第4期34卷 158-165页

作者：石敏陶思洁李丹王鑫徐水朱勇西南大学生物技术学院农业农村部蚕桑生物学与遗传育种重点实验室

以再生丝素和海藻酸钙为主要原料,通过冷冻干燥法制备再生丝素/海藻酸钙复合材料。采用扫描电镜(SEM)对八组材料断面的内部结构与形态进行了检测。同时,实验测定了材料的吸水率、保水率和力学性能,结果表明:这八组材料均具有相互连通且... 详细信息

以再生丝素和海藻酸钙为主要原料,通过冷冻干燥法制备再生丝素/海藻酸钙复合材料。采用扫描电镜(SEM)对八组材料断面的内部结构与形态进行了检测。同时,实验测定了材料的吸水率、保水率和力学性能,结果表明:这八组材料均具有相互连通且均匀分布的三维多孔结构,孔径位于50~300μm之间;吸水率在589.09%~1908.31%之间;保水率在227.34%~1542.93%之间;所有的材料均具有良好的重复使用性以及较快的吸水速率;湿态环境下的抗拉强度在0.0669~0.2375 MPa之间;断裂伸长率在0.6282~1.8092之间。通过复合材料的SD(Sprague-dawley)大鼠体内埋植试验发现,所有材料均具有生物相容性和可降解性。

关键词：蚕丝再生丝素海藻酸钙组织工程

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一种基于降采样后关键点优化的点云配准方法

计算机应用研究 2021年第3期38卷 904-907页

作者：陶四杰白瑞林江南大学物联网工程学院轻工过程先进控制教育部重点实验室江苏无锡214122

针对工件点云数据多而导致点云配准耗时长的问题,提出一种基于降采样后关键点优化的点云配准方法。计算点云若干体素的重心,利用kd-tree快速遍历重心的邻近点来代替该体素;提出自适应的点云平均距离计算方法,对降采样后的点云提取ISS3D... 详细信息

针对工件点云数据多而导致点云配准耗时长的问题,提出一种基于降采样后关键点优化的点云配准方法。计算点云若干体素的重心,利用kd-tree快速遍历重心的邻近点来代替该体素;提出自适应的点云平均距离计算方法,对降采样后的点云提取ISS3D关键点,并采用基于球邻域的边界点判断方法对其优化;对优化后的关键点进行FPFH特征描述,利用SAC-IA求解近似变换阵,使用ICP算法精配准而解得工件的精确位姿信息。实验结果表明,相较于其他四种配准算法,配准精度分别提高了96.9%、98.1%、93.3%和3.5%,配准速度分别提高了77.2%、77.7%、76.9%和85.4%,表明了该方法的有效性。

关键词：耗时体素网格关键点边界点

丝素蛋白/碳酸钙复合支架材料的制备及其理化性能

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纺织学报 2012年第3期33卷 27-33页

作者：侯春春陶思洁朱勇徐水西南大学生物技术学院重庆400715

为了研制一种力学性能和内部结构都符合人工骨要求的复合材料,本文以丝素蛋白和自制碳酸钙为原料,采用冷冻干燥法制备复合支架材料,并对其进行了理化性质测试。结果表明:样品的横截面呈蜂窝状形态结构,孔径在20～300μm之间,孔之间有微... 详细信息

为了研制一种力学性能和内部结构都符合人工骨要求的复合材料,本文以丝素蛋白和自制碳酸钙为原料,采用冷冻干燥法制备复合支架材料,并对其进行了理化性质测试。结果表明:样品的横截面呈蜂窝状形态结构,孔径在20～300μm之间,孔之间有微孔起着相互连通的作用;孔隙率在43%～76%之间。力学性能测试结果表明,样品的弹性模量在23～1 802 MPa之间,压缩强度在8～41 MPa之间。FT-IR谱图显示,样品中出现了峰的偏移、削弱和消失,可知二者发生了一定程度的复合。DSC测试表明,碳酸钙的加入促进了丝素蛋白由无规卷曲向β-折叠构象的转变,结晶度得到提高。

关键词：人工骨复合材料冷冻干燥丝素蛋白碳酸钙

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基于改进单调法的阴影区相位噪声校正方法

激光与光电子学进展 2020年第2期57卷 256-263页

作者：陶四杰白瑞林王昌龙江南大学物联网工程学院轻工过程先进控制教育部重点实验室江苏无锡214122

针对双目视觉系统中单调法校正阴影区相位噪声时存在校正不足的问题,提出了一种改进型相位校正方法。利用四步相移与多频外差求解工件表面的绝对相位信息,通过单调不减性对相位噪声进行校正。分析多组实验对象校正不足时相位噪声特点,... 详细信息

针对双目视觉系统中单调法校正阴影区相位噪声时存在校正不足的问题,提出了一种改进型相位校正方法。利用四步相移与多频外差求解工件表面的绝对相位信息,通过单调不减性对相位噪声进行校正。分析多组实验对象校正不足时相位噪声特点,根据相位频率矩阵计算固定区间内非零相位出现的频率来校正离散相位噪声,利用相邻间断点实际相位与预测相位的差值对连续相位噪声进行校正。计算间断点间的斜率与两侧非零相位的拟合斜率并进行判断,利用线性法补齐因随机噪声而被置零的部分相位,保证了工件信息的完整性。实验结果表明:所提方法可以有效校正阴影区的相位噪声,可适用于不同的实验对象,圆柱体木质工件的平均测量误差为0.0859mm,精度可满足目标抓取的位姿估计要求。

关键词：机器视觉阴影区相位校正多频外差

Precautionary Effort Investment under Cross Risk Aversion

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Journal of Systems Science and Information 2019年第4期10卷 344-358页

作者： Yuqing tao Jie MEI Wen CHENG sijie ZOU Department of Teacher Education Maanshan Teacher’s CollegeMa’anshan 243041China Class 6 Grade 1No.1 Middle School Affiliated to Central China Normal UniversityWuhan 430223China Department of Risk Management China Huarong Asset Management Co.LtdBeijing 100033China Department of Finance Shandong BranchChina Three Gorges New Energy Co.LtdJinan 277000China

This paper deals with the effort problem under multiple risks in bivariate utility setting. We identify preference conditions to insure positive or negative effect of a background variable uncertainty on effort in the presence of other risks. We allow for the simultaneous presence of wealth and background variable uncertainties. We investigate the joint effect of two-source uncertainties on effort when two risks are either small or positive quadrant dependent. Our work extends the previous model of effort to bivariate utility framework and presents new insights into the issue of optimal effort under uncertainty.

关键词： precautionary effort risks correlation risk aversion cross prudence decision-making under uncertainty

Molecular Engineering of g-C_(3)N_(4)with Dibenzothiophene Groups as Electron Donor for Enhanced Photocatalytic H_(2)-Production

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Chinese Journal of Structural Chemistry 2022年第6期41卷 48-54页

作者： Shanren tao sijie Wan Qinyang Huang Chengming Li Jiaguo Yu Shaowen Cao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The construction of donor-acceptor(D-A)molecular structure is an attractive strategy to enhance the photocatalytic performance of polymeric ***,dibenzothiophene(DBT)-4-carbaldehyde as the precursor is introduced into g-C_(3)N_(4)(TCN)prepared by two-step thermal polymerization to construct an intramolecular D-A type copolymer(TCN-DBT_(x)).DFT calculation and experimental results reveal that DBT plays the role of electron donor unit to modify g-C_(3)N_(4).The incorporation of DBT not only adjusts the band gap to improve reduction ability,but also induces an internal electric field with extendingπ-conjugated system for effective charge *** a result,TCN-DBT_(x)exhibits much better photocatalytic performance with an optimal hydrogen production rate of 3334μmol h^(-1)g^(-1),which is 2.5 times that of *** work provides a protocol for preparing high-performance g-C_(3)N_(4)-based photocatalysts toward various applications.

关键词： carbon nitride donor-acceptor photocatalysis charge transfer

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含羞草素对肝癌细胞QGY-7703周期同步化的作用

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浙江理工大学学报（自然科学版） 2016年第4期35卷 620-624页

作者：赵雪芹任磊王大巾张永明陶斯杰浙江理工大学生命科学院杭州310018 厦门大学材料学院福建厦门361005

恶性肿瘤是严重威胁人类健康的疾病之一。肿瘤的发生发展本质上就是细胞无限制的周期性生长、增殖和分化的失调。细胞同步化是研究肿瘤发生发展及治疗的基础。实验以人肝癌QGY‐7703细胞株为研究对象，考察含羞草素阻断对周期同步化的... 详细信息

恶性肿瘤是严重威胁人类健康的疾病之一。肿瘤的发生发展本质上就是细胞无限制的周期性生长、增殖和分化的失调。细胞同步化是研究肿瘤发生发展及治疗的基础。实验以人肝癌QGY‐7703细胞株为研究对象，考察含羞草素阻断对周期同步化的作用。并与胸腺嘧啶脱氧核苷阻断法相对照，研究含羞草素阻断去除后对QGY‐7703细胞周期的影响。结果显示：QGY‐7703细胞在含羞草素阻断后释放的第10 h进入S期，第20 h进入G2／M期，且最高同步率分别为G1期94．6％，S期86．0％。含羞草素能较好地使肝癌细胞株QGY‐7703同步化于G1期和S期。

关键词：含羞草素肝癌细胞细胞周期同步化