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超高效液相色谱法检验复印纸中荧光增白剂及其在文件真实性鉴定中的应用研究

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分析测试学报 2024年第9期43卷 1398-1408页

作者：李扬动赵鹏程王宗兴王逸飞吕荫妮张泽恩王千羽于郁沛何宇桓中国刑事警察学院刑事科学技术学院辽宁沈阳110854

利用超高效液相色谱法对144种A4复印纸中荧光增白剂进行鉴别并对其老化规律进行研究。采用40%乙腈水溶液作为提取剂,以含25 mmol/L四丁基溴化铵(TBA)的甲醇-水溶液(5∶95,体积比)和乙腈-甲醇混合溶液(2∶3,体积比)为流动相梯度洗脱。结... 详细信息

利用超高效液相色谱法对144种A4复印纸中荧光增白剂进行鉴别并对其老化规律进行研究。采用40%乙腈水溶液作为提取剂,以含25 mmol/L四丁基溴化铵(TBA)的甲醇-水溶液(5∶95,体积比)和乙腈-甲醇混合溶液(2∶3,体积比)为流动相梯度洗脱。结果表明,复印纸中7种常见荧光增白剂在0.5~200μg/mL范围内线性关系良好,r^(2)均大于0.999,检出限为0.03~0.08μg·mL^(-1),定量下限为0.11~0.28μg·mL^(-1);3个不同加标水平下的平均回收率为92.1%~108%,相对标准偏差(RSD)为1.6%~5.9%。在144种A4复印纸中共检出3种荧光增白剂,分别为荧光增白剂BBU、VBL和MST,依据其组成和比例将纸张样品分为8个大类,45个小类,再结合白度测量值,又可分为53种类型。相同品牌型号的纸张,克重不同,所含染料配比与含量不一定相同。选取89号、29号和28号复印纸,在紫外仪中透射老化10天,2天测量一次,3种复印纸荧光增白剂的含量和白度值均发生明显下降,证明了利用荧光增白剂检验文件制成时间的可行性。该方法前处理简单,数据稳定可靠,可为文件的真实性鉴定提供一定的参考依据。

关键词：超高效液相色谱荧光增白剂法庭科学纸张鉴别纸张老化

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基于转录因子生物传感器在环境分析中的应用

生物技术通报 2024年第6期40卷 114-125页

作者：张迪鞠睿李丽梅王煜倩陈瑞王新一大连大学生命健康学院大连116622 沈阳农业大学理学院沈阳110866 北京市科学技术研究院城市安全与环境科学研究所职业安全健康北京市重点实验室北京100054

转录因子是一类在细胞中通过引导RNA聚合酶与特定DNA序列结合调控基因表达的蛋白质。转录因子是生物体适应自然环境过程中的一类重要调节性蛋白,可专一性的感知环境介质中的配体分子。利用转录因子作为识别元件构建生物传感体系并与不... 详细信息

转录因子是一类在细胞中通过引导RNA聚合酶与特定DNA序列结合调控基因表达的蛋白质。转录因子是生物体适应自然环境过程中的一类重要调节性蛋白,可专一性的感知环境介质中的配体分子。利用转录因子作为识别元件构建生物传感体系并与不同的信号转导和放大系统耦合,可在细胞、无细胞和体外等不同反应体系构建信号输出形式灵活多样的传感策略。基于转录因子构建的生物传感器(TFBBs),因其灵敏度高、体积小、价格低廉以及可应用于现场监测等优势,在环境分析领域显示出巨大应用潜力。文中着重介绍了TFBBs的传感体系类型、核心元件组成和工作原理,列举了其在重金属离子、芳香族化合物及抗生素等环境污染物检测中的应用进展,在此基础上讨论了TFBBs在环境污染物检测中可能面临的机遇和挑战,并对其发展趋势进行了展望,指出合成生物学、人工智能等多学科新兴技术的高速发展将促进TFBBs人工设计和传感性能提升,使其应用于更广泛的领域。

关键词：转录因子生物传感环境分析重金属离子芳香族化合物抗生素

Membrane-Potential Alteration During K+ Uptake of Different Salt-Tolerant Wheat Varieties

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Agricultural Sciences in China 2010年第7期9卷 974-979页

作者： wang yu-qian wang Xiao-li SHAN yu-hua SHENG Hai-jun FENG Ke Key Laboratory of Crop Genetics and Physiology of Jiangsu Province Yangzhou University Yangzhou 225009 P.R. China School of Life Sciences Guizhou Normal University Guiyang 550001 P.R.China

K＋ is the most abundant cation in plant cells and plays an important role in many ways.K＋ uptake of plant has respect to its salt resistant *** are two categories of channel transportation for plants to uptake K＋,one is through K＋ channels and the other is through nonselective cation channels（NSCCs）.The transmembrane localization of K＋ may change membrane potential（MP）.In this paper,three wheat varieties with different salt tolerance were selected and the MP was measured by microelectrode during K＋ *** results showed that the effects of K＋ uptake on MP through K＋ channels or NSCCs were distinct.K＋ influx through K＋ channels led to MP hyperpolarization,while K＋ influx through NSCCs resulted in *** MP alteration of wheat varieties with different salt tolerance was mainly due to NSCCs-mediated K＋ *** with the salt-tolerant wheat,the MP hyperpolarization during K＋ uptake of saltsensitive wheat was much more evident,probably because of the cation outflux through NSCCs during this process.

关键词： wheat K^+ uptake nonselective cation channels (NSCCs) membrane-potential

Ammonium Effects on Nitrate Uptake by Roots of Upland and Paddy Rice Seedlings Related to Membrane Potential Differences

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Agricultural Sciences in China 2010年第6期9卷 799-805页

作者： wang Xiao-li wang yu-qian TAO yue-yue FENG Ke College of Environmental Science and Engineering Yangzhou University Yangzhou 225009 P.R. China

Nitrate uptake characteristics and ammonium effects on nitrate uptake were compared between upland rice （Brazilian upland rice） and paddy rice （Wuyujing 3 and Yangdao 6） through the glass microelectrode technique and the concentration gradient method of uptake *** indicated that nitrate uptake by rice seedlings and ammonium effects were depending on membrane potential of root *** upland rice and paddy rice presented obviously different *** all cultivars,the nitrate treatments induced rapid depolarization and then slow repolarization of membrane potential in root epidermal cells,and even hyperpolarization was observed when nitrate concentration was *** membrane potential of epidermal cells in Brazilian upland rice roots was larger and its response to NO3- was bigger than those of two paddy rice *** of membrane potential was amplified when ammonium was simultaneously added with nitrate into the measure medium,but repolarization was reduced,even *** upland rice seedlings had high Vmax of nitrate uptake and low Km,furthermore,Vmax and Km were little affected by ammonium,but Vmax of Wuyujing 3 was reduced ***,inhibition of NH4＋ differed obviously between upland rice and paddy rice.

关键词： nitrate uptake membrane potential ammonium upland rice paddy rice

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： yu Zhang Bei Gong qian wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication

基于气相色谱-质谱联用法的喷墨打印文件墨迹中挥发性溶剂历时性变化规律研究

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分析测试学报 2024年第6期43卷 858-865,874页

作者：王千羽赵鹏程崔岚宋辉李扬动张祉悦中国刑事警察学院刑事科学技术学院辽宁沈阳110035

为解决司法鉴定领域中喷墨打印文件制成时间问题,利用气相色谱-质谱联用法(GC-MS)定性定量分析4种黑色喷墨打印文件墨迹中的挥发性溶剂成分。对同一时间打印的样品进行追踪测试,每间隔一定天数用打孔器取样,提取剂提取后进行GC-MS分析... 详细信息

为解决司法鉴定领域中喷墨打印文件制成时间问题,利用气相色谱-质谱联用法(GC-MS)定性定量分析4种黑色喷墨打印文件墨迹中的挥发性溶剂成分。对同一时间打印的样品进行追踪测试,每间隔一定天数用打孔器取样,提取剂提取后进行GC-MS分析。通过内标法测定样品提取液中各组分的浓度,计算单位长度(mm)墨迹中挥发性溶剂含量C(ng/mm)并作为打印样品老化的定量单位。结果表明,4种打印样品中含有2-吡咯烷酮、1,5-戊二醇、2-甲基-1,3-丙二醇、N-羟乙基-2-吡咯烷酮、甘油和三甘醇6种挥发性溶剂成分。上述成分在文件形成时即开始挥发和转移,含量不断减少至某一数值时趋于稳定。利用测定的历经不同时间的打印样本中溶剂含量数据,建立了单组分溶剂与时间的非线性回归模型以及多组分溶剂与时间的多元线性回归模型,模型评价指标比较结果表明,对于溶剂组分数多的墨水使用多元线性回归模型的预测效果更好。

关键词：喷墨打印文件形成时间回归模型气相色谱-质谱联用法挥发性物质

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腺苷酸活化蛋白激酶在炎症性肠病的研究进展

中国现代医学杂志 2024年第8期34卷 34-39页

作者：王裕倩蓝程符永华王新月海南医学院临床学院海南海口571199 海南医学院附属海南医院消化内科海南海口570311 海南医学院第一附属医院创伤医学中心海南海口570102

炎症性肠病(IBD)是一种与炎症及免疫相关的慢性肠道疾病,发病率逐年递增,是全球卫生问题的重大挑战。但是目前IBD确切的发病机制仍未十分清楚。腺苷酸活化蛋白激酶(AMPK)是一种高度保守的细胞能量保护器,在维持体内能量平衡中发挥了十... 详细信息

炎症性肠病(IBD)是一种与炎症及免疫相关的慢性肠道疾病,发病率逐年递增,是全球卫生问题的重大挑战。但是目前IBD确切的发病机制仍未十分清楚。腺苷酸活化蛋白激酶(AMPK)是一种高度保守的细胞能量保护器,在维持体内能量平衡中发挥了十分重要的作用。近年来研究发现,AMPK可通过增强肠道屏障功能、抑制炎症反应、抗纤维化、增强自噬等方面延缓炎症性肠病疾病的进展。该文对以上方面进行综述,为IBD提供新的治疗靶点。

关键词：炎症性肠病腺苷酸活化蛋白激酶结肠炎

TRPS1在原发性乳腺外Paget病中的表达及其诊断价值

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诊断病理学杂志 2024年第9期31卷 851-854页

作者：毛学源戚玉琴佘欣远黄旭郑宇王前玉宿迁市第一人民医院病理科江苏宿迁223800

目的分析TRPS1在原发性乳腺外Paget病(EMPD)中的表达情况,探讨TRPS1在原发性EMPD诊断中的价值。方法收集宿迁市第一人民医院病理科2015年7月至2023年12月诊断的39例原发性EMPD、6例继发性EMPD、15例黑色素瘤和11例鳞状细胞原位癌病历资... 详细信息

目的分析TRPS1在原发性乳腺外Paget病(EMPD)中的表达情况,探讨TRPS1在原发性EMPD诊断中的价值。方法收集宿迁市第一人民医院病理科2015年7月至2023年12月诊断的39例原发性EMPD、6例继发性EMPD、15例黑色素瘤和11例鳞状细胞原位癌病历资料,采用免疫组织化学En Vision法检测TRPS1的表达情况。结果原发性EMPD患者39例,男性29例,女性10例;年龄53~81岁(平均年龄68岁,中位年龄71岁)。继发性EMPD患者6例,男性4例,女性2例;年龄45~76岁(平均年龄59岁,中位年龄62.5岁)。39例原发性EMPD中,35例(35/39)显示TRPS1强和弥漫的细胞核表达,阳性率为89.7%,且4例阴性病例均位于肛周;而在6例继发性EMPD中均为阴性。TRPS1在15例黑色素瘤中也呈阴性,在90.9%(10/11)的鳞状细胞原位癌中表现为弥漫强阳性。本组病例中,TRPS1诊断原发性EMPD的敏感性和特异性分别为89.7%和68.8%。结论TPRS1在原发性EMPD中的表达具有高敏感性,有助于与继发性EMPD和黑色素瘤进行鉴别,但在原发性EMPD与鳞状细胞原位癌的鉴别中作用有限。

关键词：乳腺外Paget病免疫组织化学 TRPS1 外生殖器腋窝

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Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid Phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： qian wang Peng yu Haoran Lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound