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软骨胶原蛋白肽的制备、特性及其成骨细胞增殖活性研究
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作者 张武 陈天一 +4 位作者 应顺莉 刘合生 杨华 曹少谦 戚向阳 《核农学报》 CAS 北大核心 2025年第1期107-118,共12页
为充分利用鲨鱼软骨资源,本研究以成骨细胞增殖率为指标,在优化促成骨细胞增殖胶原蛋白肽酶解工艺的基础上,分析酶解物的相对分子质量、氨基酸组成及稳定性等。结果表明,酸性蛋白酶为最优蛋白酶,且在酶添加量5 100 U·g^(-1)、料液... 为充分利用鲨鱼软骨资源,本研究以成骨细胞增殖率为指标,在优化促成骨细胞增殖胶原蛋白肽酶解工艺的基础上,分析酶解物的相对分子质量、氨基酸组成及稳定性等。结果表明,酸性蛋白酶为最优蛋白酶,且在酶添加量5 100 U·g^(-1)、料液比1∶50(g·mL^(-1))、酶解时间4.14 h和温度55℃条件下,得率为91.23%。所制酶解物促成骨细胞增殖率与水解度分别为141.23%与25.03%;鲨鱼软骨胶原蛋白肽具有一定的稳定性且对紫外光不敏感,适当加热可以提升其促成骨细胞增殖率,但温度过高会使增殖率显著下降;经胃肠模拟消化后,酶解物促成骨细胞增殖率显著下降;所制酶解物以疏水氨基酸为主,其蛋白肽分子量一般小于3 kDa,具有促进成骨细胞增殖、分化及矿化作用,以浓度1.0 mg·mL^(-1)时效果较佳。本研究可为鲨鱼资源精深加工和高值化利用提供一定理论依据。 展开更多
关键词 鲨鱼软骨 胶原蛋白肽 促成骨细胞增殖活性 制备 特性
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基于SolidWorks的选煤厂车间三维设计 被引量:14
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作者 黄波 韦彬 +1 位作者 李志勇 葛咸浩 《煤炭工程》 北大核心 2014年第3期23-25,共3页
AutoCAD二维设计在选煤厂设计过程中存在效率低和管道设计困难等缺点,三维辅助设计直接将设计者脑海中的模型,形象逼真的反映在计算机屏幕上,具有"所见即所得"的特点,可以降低管道设计难度,提升工程图纸质量和出图速度。论文... AutoCAD二维设计在选煤厂设计过程中存在效率低和管道设计困难等缺点,三维辅助设计直接将设计者脑海中的模型,形象逼真的反映在计算机屏幕上,具有"所见即所得"的特点,可以降低管道设计难度,提升工程图纸质量和出图速度。论文以宁鲁煤电有限责任公司任家庄选煤厂设计为例,探讨了基于SolidWorks的选煤厂车间三维设计的思路、步骤以及选煤厂三维设计的优势和存在的技术难点,简要说明了选煤厂三维设计的发展趋势。 展开更多
关键词 SOLIDworkS 选煤厂 三维设计 管道设计 碰撞检查
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Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis
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作者 Ze-Long Zheng Qing-Fan Zheng +1 位作者 Li-Qiang Wang Yi Liu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期13-26,共14页
The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human body.Although adequate bowel preparation can i... The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human body.Although adequate bowel preparation can improve the results of colonoscopy,it may interfere with the gut microbiota.Bowel preparation for colonoscopy can lead to transient changes in the gut microbiota,potentially affecting an individual’s health,especially in vulnerable populations,such as patients with inflammatory bowel disease.However,measures such as oral pro-biotics may ameliorate these adverse effects.We focused on the bowel prepa-ration-induced changes in the gut microbiota and host health status,hypothesized the factors influencing these changes,and attempted to identify measures that may reduce dysbiosis,thereby providing more information for individualized bowel preparation for colonoscopy in the future. 展开更多
关键词 Bowel preparation COLONOSCOPY MICROBIOTA Inflammatory bowel disease PROBIOTICS
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基于SolidWorks的选煤厂管道设计 被引量:11
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作者 黄波 韦彬 +1 位作者 李志勇 葛咸浩 《煤炭工程》 北大核心 2014年第10期91-93,共3页
传统选煤厂二维管道设计过程中存在设计效率低下及难以发现管道碰撞等问题,三维管道设计具有"所见即所得"的直观表达方式和强大的碰撞检查功能可以有效降低管道设计难度,提升管道设计效率。论文以安家岭二号矿井选煤厂管道设... 传统选煤厂二维管道设计过程中存在设计效率低下及难以发现管道碰撞等问题,三维管道设计具有"所见即所得"的直观表达方式和强大的碰撞检查功能可以有效降低管道设计难度,提升管道设计效率。论文以安家岭二号矿井选煤厂管道设计为例探讨了基于SolidWorks的选煤厂三维管道设计的思路和步骤、选煤厂三维管道设计的优势和存在的技术难点,简要说明了选煤厂三维管道设计的发展趋势。 展开更多
关键词 管道设计 SOLIDworkS 三维设计 选煤厂设计 碰撞检查
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Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives
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作者 Shuo Chen Shengpeng Su +4 位作者 Yanfang Huang Bingbing Liu Hu Sun Shuzhen Yang Guihong Han 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期1-19,共19页
Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and ... Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental safety.Neoteric solvents have been recognized as potential alternatives to these harmful organic solvents.In the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low cost.In this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically described.Subsequently,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively summarized.Finally,future opportunities and challenges of DESs were explored in the current research area.In conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy. 展开更多
关键词 deep eutectic solvents preparations PROPERTIES separation and purification critical metal metallurgy
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不同烫漂方式及冷冻速率对预制西兰花质构品质的影响
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作者 赵伊诺 金鑫 +2 位作者 毕金峰 谢意通 杜婷 《食品科学》 EI CAS 北大核心 2025年第1期121-130,共10页
为探究预制西兰花加工过程中烫漂方式及冷冻速率对西兰花质构品质的影响,对经2种烫漂方式(热水烫漂、蒸汽烫漂)及3种冷冻温度(-20、-40、-80℃)处理的西兰花样品,利用低场核磁共振、理化特性分析方法测定不同处理组样品的水分分布、持... 为探究预制西兰花加工过程中烫漂方式及冷冻速率对西兰花质构品质的影响,对经2种烫漂方式(热水烫漂、蒸汽烫漂)及3种冷冻温度(-20、-40、-80℃)处理的西兰花样品,利用低场核磁共振、理化特性分析方法测定不同处理组样品的水分分布、持水性、相对电导率和硬度,观察微观结构。结果表明:维持西兰花硬度的最佳工艺为蒸汽烫漂后进行-40℃冷冻,在此工艺条件下,与对照组相比,处理组西兰花水分分布中结合水峰面积占比(A21)增加最多、持水性最强,花序部分保留66.72%硬度、茎部分保留62.53%硬度,相对电导率增加至87.01%;通过扫描电子显微镜观察发现,经过该处理的西兰花保持了较好的细胞结构。本研究得到了有效维持解冻西兰花质构的工艺,并揭示了不同处理对西兰花水分分布及细胞膜完整性影响的机制,为实际生产过程保持冷冻预制西兰花品质提供了理论与技术支撑。 展开更多
关键词 预制西兰花 持水性 水分迁移 质构
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基于SolidWorks的选煤非标件参数化设计 被引量:2
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作者 肖林京 马成瀚 +3 位作者 张玉龙 庞冲 曹畅 谷振玲 《煤炭技术》 CAS 北大核心 2021年第11期208-210,共3页
为解决传统的选煤非标件设计过程繁琐,设计周期长的难题,提出了以SolidWorks软件为基础的选煤非标件辅助设计软件开发。首先用SolidWorks方程式功能建立选煤非标件的三维模型模板,然后采用C#编程语言对SolidWorks进行二次开发。该辅助... 为解决传统的选煤非标件设计过程繁琐,设计周期长的难题,提出了以SolidWorks软件为基础的选煤非标件辅助设计软件开发。首先用SolidWorks方程式功能建立选煤非标件的三维模型模板,然后采用C#编程语言对SolidWorks进行二次开发。该辅助设计软件能够大幅度降低选煤非标件设计难度,实现了三维模型的快速设计和工程出图。 展开更多
关键词 SOLIDworkS 二次开发 选煤非标件 参数化设计
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基于Solidworks的选煤厂工业场地三维辅助设计 被引量:4
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作者 吴翠平 丁清珍 +2 位作者 路阳 张俱嘉 郭永昌 《选煤技术》 CAS 2015年第6期85-88,共4页
三维设计已成为选煤厂工程设计的发展趋势。针对我国目前仍缺乏针对选煤行业的专用三维设计工具的情况,对通用三维设计软件进行了本地化地二次开发。以VB作为开发语言对Solid Works进行了二次开发,根据选煤厂工业场地内建筑物/构筑物设... 三维设计已成为选煤厂工程设计的发展趋势。针对我国目前仍缺乏针对选煤行业的专用三维设计工具的情况,对通用三维设计软件进行了本地化地二次开发。以VB作为开发语言对Solid Works进行了二次开发,根据选煤厂工业场地内建筑物/构筑物设计计算的参数实时改变模型尺寸,探索了变量化设计、三维建模绘图的实现方法。研究结果表明:变量化设计方法可省去繁琐的绘图步骤,有效提高选煤厂三维设计效率。 展开更多
关键词 选煤厂设计 三维辅助设计 SOLIDworkS 二次开发
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SolidWorks的选煤厂设备联系图二次开发 被引量:1
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作者 吴翠平 丁清珍 +1 位作者 朱志波 毛盼盼 《煤炭技术》 CAS 北大核心 2015年第7期231-234,共4页
以Visual Basic为开发语言,利用宏录制功能辅助SolidWorks的二次开发,研究SolidWorks二次开发在选煤厂设计中应用的技术途径。具体讨论选煤厂设备联系图辅助绘制中界面、图符库的二次开发方法,并给出应用实例。证实通过调用设备图符库... 以Visual Basic为开发语言,利用宏录制功能辅助SolidWorks的二次开发,研究SolidWorks二次开发在选煤厂设计中应用的技术途径。具体讨论选煤厂设备联系图辅助绘制中界面、图符库的二次开发方法,并给出应用实例。证实通过调用设备图符库绘制选煤设备联系图,能提高绘制效率。 展开更多
关键词 SOLIDworkS 二次开发 VB 选煤厂设备联系图
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基于“SolidWorks”软件的“Flow Simulation”插件选择分散盘 被引量:10
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作者 陈璟 周金卿 +5 位作者 李行可 余恒建 叶朝霞 梁健 邓昌建 陈龙 《中国胶粘剂》 CAS 北大核心 2013年第12期13-16,共4页
应用"SolidWorks"软件的"Flow Simulation"插件对胶粘剂制备过程中所需分散盘周围的流场进行了CFD(计算流体动力学)分析。研究结果表明:通过仿真分析,可直观获得反应混合釜内流体的速度云图和流线轨迹;采用粒子轨... 应用"SolidWorks"软件的"Flow Simulation"插件对胶粘剂制备过程中所需分散盘周围的流场进行了CFD(计算流体动力学)分析。研究结果表明:通过仿真分析,可直观获得反应混合釜内流体的速度云图和流线轨迹;采用粒子轨迹示踪法可模拟胶粘剂制造过程中原料在分散盘作用下的分布,并可有效预测3种不同分散盘对胶液的分散效果,以便于在实际胶粘剂制造过程中选择最佳的分散盘。 展开更多
关键词 胶粘剂 制备 分散盘 流体分析 计算流体动力学 FLOW SIMULATION
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四个京药制剂稳定性试验研究
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作者 周家福 吴晓燕 易冰 《中国中医药现代远程教育》 2025年第2期97-100,共4页
京族是广西特有且以海为生的海洋少数民族,其民间经方、验方逐渐被遗忘,故开展抢救和挖掘工作迫在眉睫。文章在京族特色经验方的基础上,筛选出治疗外伤、胃病、痹症的京药顺气护胃方、京药补肾壮骨方、京药血府逐瘀方和京药骨外伤方,并... 京族是广西特有且以海为生的海洋少数民族,其民间经方、验方逐渐被遗忘,故开展抢救和挖掘工作迫在眉睫。文章在京族特色经验方的基础上,筛选出治疗外伤、胃病、痹症的京药顺气护胃方、京药补肾壮骨方、京药血府逐瘀方和京药骨外伤方,并通过四种特色京药制剂的研发,确定了制剂原料标准、各组分比例,实现了标准化生产,相比于传统中药汤剂,大大提高了中药用法的一致性、稳定性、便捷性。希望对挖掘、整理京药有效民间方及开发医疗机构制剂起到重要示范作用,为中药新药研究打下良好基础。 展开更多
关键词 京药 京药顺气护胃方 京药补肾壮骨方 京药血府逐瘀方 京药骨外伤方 稳定性试验
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固态胶原基材料在医疗器械中的应用
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作者 胡张捷 张宝贯 张智武 《中国组织工程研究》 CAS 北大核心 2025年第16期3503-3512,共10页
背景:胶原蛋白是细胞外基质的主要构成成分,具有稳定的三螺旋结构特性、良好的生物学特性和可加工性,是一种理想的生物医用材料,已被广泛应用于医疗器械领域。目的:分析固态胶原基材料的主要产品形态、技术特点、制备工艺和临床应用。方... 背景:胶原蛋白是细胞外基质的主要构成成分,具有稳定的三螺旋结构特性、良好的生物学特性和可加工性,是一种理想的生物医用材料,已被广泛应用于医疗器械领域。目的:分析固态胶原基材料的主要产品形态、技术特点、制备工艺和临床应用。方法:应用计算机检索PubMed和中国知网数据库收录的有关固态胶原基材料在医疗器械领域应用的研究,英文检索词为“collagen,collagen sponge,collagen membrane,collagen powder,collagen gel,decellularized extracellular martix,medical device,clinical application”,中文检索词为“胶原,胶原海绵,胶原膜,胶原粉,胶原凝胶,脱细胞基质,医疗器械,临床应用”。根据纳入与排除标准对所有文章进行初筛后,保留质量和相关性较高的92篇文献进行综述。结果与结论:以动物源来源固态胶原基材料作为医疗器械制备材料,已在原料提取、制备工艺及临床应用等方面取得显著进展,海洋生物胶原和重组胶原增加了胶原来源的可选择性。固态胶原基医疗器械产品类型丰富,制备方法多样,其中交联改性是提升材料性能的重要途径,值得被深入研究。在产品开发思路上,固态胶原基医疗器械产品研究正朝着立体化和仿生化方向发展,与其他生物材料、药物复合的研究也展现出巨大潜力。尽管国内已有不少胶原基医疗器械应用于临床,但在人工皮肤、软骨修复和神经损伤修复等领域的产品开发仍显不足,需在技术和产业化上进一步突破与创新。 展开更多
关键词 胶原蛋白 固态胶原 生物学特性 医疗器械 制备工艺 临床应用
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有限元分析牙髓根尖周病根管治疗中的牙体力学性能
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作者 杨文静 格根塔娜 《中国组织工程研究》 CAS 北大核心 2025年第20期4295-4304,共10页
背景:根管治疗后牙髓根尖周病变患牙往往因失去较多健康牙体组织等原因导致抗折强度降低,如何增强牙齿抗折强度一直是临床医生密切关注的问题。有限元分析能直观地展示不同状态下患牙各个部分的受力情况,对牙体结构和材料力学性能等进... 背景:根管治疗后牙髓根尖周病变患牙往往因失去较多健康牙体组织等原因导致抗折强度降低,如何增强牙齿抗折强度一直是临床医生密切关注的问题。有限元分析能直观地展示不同状态下患牙各个部分的受力情况,对牙体结构和材料力学性能等进行综合分析。目的:综述有限元分析在牙髓根尖周病根管治疗中的应用进展,并对未来的发展趋势进行展望。方法:在PubMed、Web of Science数据库和中国知网、万方数据库、维普数据库、中国生物医学文献服务系统中检索使用有限元法分析牙髓根尖周病根管治疗的相关文献,英文检索词为“FEA,finite element analysis,stress analysis,root canal treatment,pulp opening,root canal preparation,root canal filling,restoration”,中文检索词为“有限元分析,应力分析,牙髓根尖周病,根管治疗,开髓,根管预备,根管充填,修复”,最终纳入103篇文献进行综述。结果与结论:有限元分析可以通过构建牙体及周围组织的有限元模型分析牙齿在咀嚼、咬合等过程中的应力分布和变形情况。借助有限元分析,临床研究者能够对牙髓根尖周病根管治疗中不同开髓洞型、根管预备方式、根管充填材料及修复方案等对牙体力学性能的影响进行分析,从而选择出最佳的治疗方案,提高治疗效果和患者预后。有限元分析有助于医生在临床治疗中减少牙体组织的损失,提高治疗效果和患者预后。有限元模型是对实际情况的简化,需结合临床试验进行综合分析。 展开更多
关键词 有限元分析 应力分析 牙髓根尖周病 根管治疗 开髓 根管预备 根管充填 修复 工程化口腔材料
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Influence of the Preparative History on Physico-chemical Properties of Sodium Aluminate Solutions 被引量:8
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作者 陈念贻 柳妙修 杨金秀 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1992年第2期135-137,共3页
1.IntroductionSodium aluminate solutions are veryimportant intermediate products in alumin-ium metallurgy.The physico-chemicalproperties of sodium aluminate solutions areconcerned by metallurgists and engineersdealing... 1.IntroductionSodium aluminate solutions are veryimportant intermediate products in alumin-ium metallurgy.The physico-chemicalproperties of sodium aluminate solutions areconcerned by metallurgists and engineersdealing with alumina production[1].Thedata of viscosity,electroconductivity,UV 展开更多
关键词 sodium aluminate solution physicochemical properties preparative history
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Tooth anatomy risk factors influencing root canal working length accessibility 被引量:9
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作者 Lu Tang Tuo-qi Sun +2 位作者 Xiao-jie Gao Xue-dong Zhou Ding-ming Huang 《International Journal of Oral Science》 SCIE CAS CSCD 2011年第3期135-140,共6页
The aim of this study was to analyze the specific influence of root canal anatomy on the accessibility of working length during root canal therapy. Four hundred seventy-six root canal therapy cases (amounting to a to... The aim of this study was to analyze the specific influence of root canal anatomy on the accessibility of working length during root canal therapy. Four hundred seventy-six root canal therapy cases (amounting to a total of 1 005 root canals) were examined. The anatomy risk factors assessed in each case included: tooth type (tooth location), root canal curvature, and root canal calcification, as well as endodontic retreatment. The investigation examined the correlation between each of these anatomic factors and the working length, with statistical analysis consisting of Chi-square tests and multiple logistic regression analysis. In an independent factor analysis, tooth type (tooth iocation), root canal curvature, canal calcification, and endodontic retreatment were determined to be the primary risk factors. In a multiple-factor regression model, root curvature and canal calcification were found to most significantly influence root canal working length accessibility (P〈0.05). Root canal anatomy increases the difficulty of root canal preparation. Appropriate consideration of tooth anatomy will assist in accurate determination of preparation difficulty before instrumentation. This study alerts clinical therapists to anatomical factors influencing the working length accessibility, and allows for a direct estimate of success rate given in situ measurements of tooth factors during the root canal treatment procedure. 展开更多
关键词 root canal anatomy root canal preparation root canal treatment working length
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解冻方式对新疆干辣椒炒牛肉预制菜品质的影响
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作者 顾雪敏 陈昆 +5 位作者 马慧 王洪旭 梅洁 王梓棚 李文凤 孔令明 《核农学报》 CAS 北大核心 2025年第1期96-106,共11页
为探究解冻方式对新疆干辣椒炒牛肉预制菜品质的影响,本研究选取自然解冻、流水解冻、超声波解冻、微波解冻和低温解冻作为解冻方式,分析5种解冻方式对新疆干辣椒炒牛肉预制菜pH值、色泽、质构特性、挥发性盐基氮(TVB-N值)、硫代巴比妥... 为探究解冻方式对新疆干辣椒炒牛肉预制菜品质的影响,本研究选取自然解冻、流水解冻、超声波解冻、微波解冻和低温解冻作为解冻方式,分析5种解冻方式对新疆干辣椒炒牛肉预制菜pH值、色泽、质构特性、挥发性盐基氮(TVB-N值)、硫代巴比妥酸值(TBARS值)和挥发性风味物质品质指标的影响。结果表明,与空白对照组相比,低温解冻在维持新疆干辣椒炒牛肉预制菜pH值(5.19)和色泽方面表现最佳,超声波解冻的质构特性最好且TVB-N值最低(7.35 mg·100 g^(-1)),微波解冻的TBARS值最低(0.36 mg·kg^(-1)),微波解冻和低温解冻后新疆干辣椒炒牛肉预制菜的感官评分较好,流水解冻各项指标处于中间位置。D-柠檬烯、苯甲醛、苯乙醛、壬醛、芳樟醇、苯乙醇、α-松油醇、3-甲基-苯酚、萘、茴香脑、草蒿脑等挥发性风味物质对新疆干辣椒炒牛肉预制菜总体风味的形成有重要贡献,低温解冻后的挥发性风味物质最接近空白对照组。本研究可为新疆干辣椒炒牛肉预制菜的解冻工艺提供支撑。 展开更多
关键词 解冻方式 预制菜 品质 挥发性风味物质 气相色谱-质谱法(GC-MS)
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INFLUENCE OF PREPARATIVE HISTORY ON STRUCTURE AND PROPERTIES OF SODIUM ALUMINATE SOLUTIONS 被引量:8
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作者 Chen Nianyi Liu Miaoxiu +1 位作者 Yang Jinxiu Chi Likuan 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1992年第2期28-31,共4页
It has been found that samples of sodium aluminate solutions with the same composition but different preparative history may have difTerent structure and physico-chemical properties.The structure of sodium-bearing alu... It has been found that samples of sodium aluminate solutions with the same composition but different preparative history may have difTerent structure and physico-chemical properties.The structure of sodium-bearing aluminate solutions change very slowly during the storage after preparation.Sodium aluminate solutions contain several ammunium-bearing anisons such as Al(OH)^(-)_(4),Al(OH)^(3-)_(6)and[(HO)_(3)Al-O-Al(OH)_(3)]^(2-),etc.These anions can convert to each other but the reactions are very slow owing to the formation or breakage of covalent Al-O bond.Hence the ratio between these anions approaches equilibrium very slowly after the preparation,and the structure or properties of these solution samples before equilibrium is reached depend on their preparative histosive. 展开更多
关键词 sodium aluminate solutions physico-chemical properties STRUCTURE preparative history
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State of the Art and Prospects in Metal-Organic Framework-Derived Microwave Absorption Materials 被引量:12
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作者 Shuning Ren Haojie Yu +6 位作者 Li Wang Zhikun Huang Tengfei Lin Yudi Huang Jian Yang Yichuan Hong Jinyi Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第4期238-276,共39页
Microwave has been widely used in many fields,including communication,medical treatment and military industry;however,the corresponding generated radiations have been novel hazardous sources of pollution threating hu... Microwave has been widely used in many fields,including communication,medical treatment and military industry;however,the corresponding generated radiations have been novel hazardous sources of pollution threating human’s daily life.Therefore,designing high-performance microwave absorption materials(MAMs)has become an indispensable requirement.Recently,metal-organic frameworks(MOFs)have been considered as one of the most ideal precursor candidates of MAMs because of their tunable structure,high porosity and large specific surface area.Usually,MOF-derived MAMs exhibit excellent electrical conductivity,good magnetism and sufficient defects and interfaces,providing obvious merits in both impedance matching and microwave loss.In this review,the recent research progresses on MOF-derived MAMs were profoundly reviewed,including the categories of MOFs and MOF composites precursors,design principles,preparation methods and the relationship between mechanisms of microwave absorption and microstructures of MAMs.Finally,the current challenges and prospects for future opportunities of MOF-derived MAMs are also discussed. 展开更多
关键词 Microwave absorption materials Metal-organic frameworks Preparation methods Mechanisms of microwave absorption
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Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction 被引量:1
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作者 LI Cun-man XIAO Yuan-sheng +3 位作者 XUE Xing-ya FENG Jia-tao ZHANG Xiu-li LIANG Xin-miao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期392-396,共5页
An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matog... An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products. 展开更多
关键词 Unstable compound Isolation and purification preparative high performance liquid chromatography Solid-phase extraction Iridoid glucoside
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A Secure Framework for Blockchain Transactions Protection 被引量:1
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作者 Wafaa N.Al-Sharu Majdi K.Qabalin +1 位作者 Muawya Naser Omar A.Saraerh 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1095-1111,共17页
One of the most extensively used technologies for improving the security of IoT devices is blockchain technology.It is a new technology that can be utilized to boost the security.It is a decentralized peer-to-peer net... One of the most extensively used technologies for improving the security of IoT devices is blockchain technology.It is a new technology that can be utilized to boost the security.It is a decentralized peer-to-peer network with no central authority.Multiple nodes on the network mine or verify the data recorded on the Blockchain.It is a distributed ledger that may be used to keep track of transactions between several parties.No one can tamper with the data on the blockchain since it is unchangeable.Because the blocks are connected by hashes,the transaction data is safe.It is managed by a system that is based on the consensus of network users rather than a central authority.The immutability and tamper-proof nature of blockchain security is based on asymmetric cryptography and hashing.Furthermore,Blockchain has an immutable and tamper-proof smart contract,which is a logic that enforces the Blockchain’s laws.There is a conflict between the privacy protection needs of cyber-security threat intelligent(CTI)sharing and the necessity to establish a comprehensive attack chain during blockchain transactions.This paper presents a blockchain-based data sharing paradigm that protects the privacy of CTI sharing parties while also preventing unlawful sharing and ensuring the benefit of legitimate sharing parties.It builds a full attack chain using encrypted threat intelligence and exploits the blockchain’s backtracking capacity to finish the decryption of the threat source in the attack chain.Smart contracts are also used to send automatic early warning replies to possible attack targets.Simulation tests are used to verify the feasibility and efficacy of the suggested model. 展开更多
关键词 MANUSCRIPT preparation typeset FORMAT
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