原位被动采样技术*

本文介绍了近些年来环境监测中三种新的原位被动采样技术-透析装置（Dialysis peepers）法、薄膜扩散平衡 (DET) 技术和薄膜扩散梯度 (DGT) 技术。综述了三种技术的原理、装置和特点。着重论述了三种技术在环境中的应用研究,包括透析装置以及DET 技术和DGT联用技术测量水体和沉积物孔隙水中可溶性金属的浓度;DGT技术可以作为一种预测重金属生物可利用性的新方法。DGT技术与其他技术（如DET、高离子选择电极、配体交换法、HPLC-ICP-MS等）联用可以更好地测量环境中重金属的形态。最后展望了原位被动采样技术未来的发展。     

龙须菜的无菌处理及其典型附生菌的分离鉴定

采用不同浓度的氨苄青霉素、卡那霉素、氯霉素以及放线菌酮单独及组合处理龙须菜, 利用16S rRNA基因序列和ITS序列对分离到的细菌和真菌进行分子鉴定, 比较获得无菌龙须菜的最佳抗生素处理方法. 结果表明: 100μg?mL-1氯霉素、100μg?mL-1氨苄青霉素及50μg?mL-1放线菌酮组合使用抑菌效果最好. 并从龙须菜的培养液中分离鉴定出4株细菌, 分别为鲁杰氏菌属(Ruegeria)、单胞菌属(Alteromonas)、Maribacter属和Fluviimonas属, 1株真菌为Urocystales或Fereydounia属, 其中鲁杰氏菌为龙须菜附生细菌的优势菌群.     

墨粉灌装车间噪声测试分析与控制

本文应用峰值频率声压级对比方法并结合相干分析技术对某墨粉灌装车间主噪声源进行了诊断，分析了声源特性，在此基础上提出了经济合理的治理措施，实施后取得了满意的结果，车间噪声达到了相应的国家标准。     

Synthesis,Crystal Structure and Luminescent Mechanochromism of a Square-planar Pt(Ⅱ) Complex Based on 1,10-Phenanthroline Derivative

A new square-planar platinum(Ⅱ) complex, [Pt(Me3SiC≡Cphen)(C≡CC6H4Cl-3)2](1), was synthesized by using 3-trimethylsilylethynyl-1,10-phenanthroline(Me3SiC≡Cphen) and 3-chlorophenylacetylene ligands, and its structure was characterized by single-crystal X-ray crystallography. 1 crystallizes in triclinic, space group P1 with a = 6.9524(5), b = 12.7796(11), c = 17.5846(10) ?, α = 78.484(5), β = 88.700(5), γ = 75.600(6)°, V = 1482.23(19) ?3, Z = 2, C33H24Cl2N2 PtSi, Mr = 742.62, Dc = 1.664 g/cm3, F(000) = 724, μ(Mo Ka) = 4.979 mm-1, R = 0.0369 and wR = 0.0786. In 1, adjacent molecules along the a axis are stacked in a columnar structure through π···π interactions, and such neighboring columnar structures are connected with each other by C–H···π hydrogen bonds to form a 2D supramolecular network. 1 exhibits reversible luminescence mechanochromic property with the luminescence red shift in a range of ca. 146~182 nm. Extremely large red-shifts of luminescence spectra suggest that luminescent mechanochromic property of 1 is due to the formation of aggregate via Pt–Pt interaction during the mechanical grinding. Based on this property, a simple device was developed and used for rewritable data storage.     

切割那些事

正祝你生日快乐,祝你生日快乐,祝你生日快乐!吹蜡烛喽,噗!贝卡,是我生日哎,你一口气把蜡烛吹灭了,几个意思啊?乔乔,那个……我是太激动了,一不小心……这样吧,我来替你切蛋糕。你想切成几块呢?(夺过塑料刀)贝卡你辛苦了,切蛋糕就不用你代劳啦!数学制造出了各种奇异的数字模式,有意思的是,你可以通过几个大小一样的球,轻松地检验它们是否正确。如果你只是一个普通人,那么你可以使用橘子或弹珠;但如果你是一位无所不     

多指示剂标记适体探针卡那霉素传感器的电化学行为与分析性能

以三分子亚甲基蓝(MB)标记适体探针为分子识别元件,构建了一种卡那霉素生物传感器.该传感器采用目标物诱导探针构型变化的信号转导机制.以Au-S化学法将适体探针自组装于金电极表面形成稳定的单分子层传感界面,利用交流伏安法和循环伏安法考察了传感过程的基础电化学行为和传感器分析性能.在优化条件下,相比于单分子MB标记,该传感...     

靶向性调控胫骨前肌对静态平衡的影响——基于经颅直流电刺激的干预

目的 采用随机、双盲交叉实验设计，探究经颅直流电刺激(transcranial direct current stimulation, tDCS)对胫骨前肌的靶向性调控是否可以诱导静态平衡表现的改善。方法 使用经颅磁刺激(transcranial magnetic stimulation, TMS)确定胫骨前的肌皮层热点靶区，24名在校大学生以随机的顺序接受两次刺激——20 min, 2 mA tDCS和假刺激(sham),每次刺激前后分别完成TMS测试和平衡能力测试，评估tDCS靶向性调控胫骨前肌对皮层兴奋性以及双足睁眼、双足闭眼、单足睁眼和单足闭眼静态平衡的影响。结果 (1)tDCS和Sham未呈现明显的组间差异；相比基线，tDCS刺激显著增大双足睁眼的平均速度，显著降低单足闭眼的动摇总轨迹长。(2)相比Sham, tDCS显著增大双足睁眼和单足闭眼Y方向平均中心变位。相比基线，tDCS显著降低双足睁眼Y方向平均中心变位、单足闭眼Y方向平均速度。(3)相比Sham, tDCS显著增加双足睁眼X方向平均中心变位、单足闭眼X方向平均中心变位和双足睁眼X方向最大动摇经。相比基线，tDCS...     

Determination of periodontal pathogens in human oral cavityEI北大核心CSCD

The simultaneous detection of Porphyromonas gingivalis （PG），Tannerela forsythia （TF），and Treponema dentinarum（TD）based on multiplex polymerase chain reaction（PCR）and capillary electrophoresis （CE），and the effect of sampling position were investigated. Results demonstrated that there was a linear relationship between migration time and DNA length when DNA fragments were separated by capillary electrophoresis，and the correlation coefficient was 0.9976. In 0.5% hydroxyethyl cellulose （HEC），the PCR products of these periodontal pathogens could be separated within 1.6 min. When sampling at different positions in the periodontal pocket，the PCR products were also different. When analyzing PCR products by capillary electrophoresis，the maximum relative deviation of the peak time was 7.4%. Based on fluorescence intensity，it could be inferred that the concentrations of PG，TD and TF in the gingival fluid were 5.13×10-11 ，7.89×10-11 and 4.87×10-11 ng/µμL，respectively. © 2023, Youke Publishing Co.,Ltd. All rights reserved.