1998年分析化学与应用光谱学匹兹堡会议(Pittcon''''98)简介

1998年分析化学和应用光谱学匹兹堡会议(Pittcon'98)于1998年3月 1日至15日在美国路易斯安那州新     

1997年分析化学与应用光谱学匹兹堡会议（Pittcon‘97）论文评述

１９９７年分析化学与应用光谱学匹兹堡会议（Ｐｉｔｃｏｎ’９７）论文评述胡军（武汉大学分析测试中心武汉４３００７２）１９９７年分析化学和应用光谱学匹兹堡会议（Ｐｉｔｃｏｎ’９７）于１９９７年３月１６日至２１日在美国亚特兰大州乔治亚市的乔治亚世界会议中心...     

CO在Pd系双金属及其单金属催化剂上的吸脱附红外光谱

红外光谱表明吸附在担载于Al_2O_3上的Pd-Cu、Pd-Ag、Pd-Co和Pd-Pt 双组分催化剂上的CO仍保持其在单金属上的主要吸附物种,但其部分CO吸收带发生位移,吸附的CO易于脱附.CO在还原态Pd-Cu和Pd-Ag双金属催化剂上以吸附于Pd上者为主,其吸收带明显变弱而更易脱附.在Pd- Pt和Pd-Co氧化和还原态催化剂上CO桥式和线式吸收带强度比发生显著变化.似乎在这二类双金属催化剂上的几何结构效应比电子配位效应更为明显.     

分子光谱学在若干应用领域的最近进展

七十年代初,随着计算机及激光技术的兴起,分子光谱学有了一个划时代的进步。从整体上看,随着量子化学、微观动力学、非平衡态统计理论、非线性光学和辐射场的量子理论与分子光谱学日益深入的相互促进,以及迅速发展的高技术的应用,近十年除分子光谱学科本身的内容极大地丰富之外,另一个突出特点是与其他分子科学有着广泛的交叉和渗透。其中尤为瞩目的是在表面科学和生命科学中的发展及其成就。纵观八十年代,分子光谱学的发展突出地呈现以下三大特征。(1)研究动态结构及过程:应用时间分辨技术,深入地探索分子动态过程和微观反应动力学。目前最高时间分辨率已优于10~(-12)秒。(2)精细的和极端条件下的分子结构:由于光谱学分辨率发展到很高的水平,不断发现新的谱带精细结构。目前激光光谱饱和谱学分辨率(Δv/v)已达10~(-15)数量级,为研究分子相互作用提供了实验基础。(3)     

2000年匹茨堡分析化学暨应用光谱学会议记盛

20 0 0年 Pittcon会议于 3月 1 2日至 1 7日在新奥尔良市召开 ,主题是“为了 2 1世纪的科学”。大会报告的题目是“以激光为基础的化学分析”。分组专题报告共 1 430个 ,墙报论文 675篇。在众多专题报告中以高效液相色谱法、毛细管电泳法、气相色谱法、质谱分析法及其联用技术和电化学分析法等分析技术为主。如按分析对象分类 ,则环境分析和生物分析占绝大多数 ,其次为食品分析。大会报告指出 :激光已成为分析仪器众多新进展的“发动机”,如激光荧光法、激光诱导光栅光谱法、激光倍增吸光度法等 ,在新世纪内激光技术和激光器类型的进展正方…     

Hβ沸石及其稀土改性后红外光谱研究

用红外光谱(IR)研究了Hβ沸石和稀土(La、Ce、Nd)氧化物改性的Hβ沸石,同时测定了苯-异丙醇烷基化反应后的Hβ沸石和La-Hβ沸石的红外光谱。考察了吸附吡啶后不同温度脱附时1545cm~(-1)吸收峰(Bronsted酸)和1454cm~(-1)吸收峰(Lewis酸)强度的变化。实验发现,在波数为3615cm~(-1)和3740cm~(-1)处有两个表示OH基振动的谱峰,前者与Bronsted酸相对应,酸性较强。稀土氧化物改性降低了B酸量,增加了L酸量,而且在波数为1603cm~(-1)和1445cm~(-1)处出现两个新的吸收峰。本文讨论了苯-异丙醇烷基化反应活性、稳定性与沸石表面酸性质的关系。     

CuO／γ—Al2O3上CO和NO吸附的红外光谱研究：Ⅱ.还原态

应用红外光谱技术研究了CO和NO及其混合气体在还原态CuO/γ-Al_2O_3上的吸附.XRD分析样品物相仅有Cu~0,但是,XPS和IR都证明样品表面上除Cu~0外,还有Cu~(2+)和Cu~+。CO以分子态的形式吸附在Cu~+和Cu~0上(低于173K,无NO存在时,CO可以吸附在Cu~(2+)上);NO以分子态吸附在Cu~(2+)上,在Cu~0上为离解吸附(173K以下,无CO存在时,NO可以吸附在Cu~+上)。CO吸附时,表面还生成HCO_3~-、CO_3~(2-)、HCOO~-,NO吸附时,除被氧化为NO3~-外,表面上还出现N_2O物种;高于室温时,CO和NO共吸附,表面上除生成HCO_3~-、CO_3~(2-)和N_2O外,还有NCO~-物种生成,讨沦了CO和NO反应的基本步骤。     

2015年化学学科发展专题论坛(续)世纪之交的分析科学——回顾与思考

本文对分析科学某些方面近年来取得的进展及其发展趋势作了综述。     

N-甲基甲酰胺与醇的氢键相互作用

Amides are used as synthetic reagents and as starting mate- rials for the preparation of insecticides and pharmaceuticals products[1]. Alcohols are industrially and scientifically important organic compounds, and their physical and chemical properties are…     

巯基修饰寡聚DNA诱导的具有光学各向异性的金纳米粒子组装体

Two complemental 2′-phosphorothioate oligo-DNA compounds were used as linker molecules to provide the necessary symmetry-breaking mechanism to direct the assembly of 13 nm Au nanoparticles into aggregates with anisotropic optical properties.     

激光光热光谱分析特性比较

本文详细比较了激光光热偏转,激光热透镜和激光光热折射光谱法的基本原理,光学构型和分析化学特性。并讨论了激光光热光谱法的分析现状和应用潜力。     

Photothermal performance of MFe2O4 nanoparticles

In this paper, we synthesized three kinds of ferrites and investigated their photothermal property. The result indicated that the photothermal effect of Fe₃O₄ and MnFe₂O₄ nanoparticles declined while that of ZnFe₂O₄ nanoparticles maintained relatively stable after preservation for 70 days, and then ZnFe₂O₄ nanoparticles could effectively kill cancer cells under NIR laser.     

Photothermal performance of MFe2O4 nanoparticles

Photothermal therapy (PTT) has emerged as one of the promising cancer therapy approaches. As a representative photothermal agent (PTA), magnetite possesses many advantages such as biodegradability and biocompatibility. However, photothermal instability hampers its further application. Herein, we systematically synthesized three kinds of ferrite nanoparticles and detailedly investigated their photothermal effect. Compared with Fe₃O₄ and MnFe₂O₄ nanoparticles, ZnFe₂O₄ nanoparticles exhibited a superior photothermal effect. After preservation for 70 days, the photothermal effect of Fe₃O₄ and MnFe₂O₄ nanoparticles observably declined while ZnFe₂O₄ nanoparticles showed slight decrease. Furthermore, in vitro experiment, ZnFe₂O₄ nanoparticles showed little toxicity to cells and achieved outstanding effect in killing cancer cells under NIR laser irradiation. Overall, through synthesizing and studying three kinds of ferrite MFe₂O₄ nanoparticles, we obtained ferrites as PTAs and learned about their changing trend in photothermal effect, expecting it can inspire further exploration of photothermal agents.     

A photosensitizer-loaded zinc oxide-polydopamine core-shell nanotherapeutic agent for photodynamic and photothermal synergistic therapy of cancer cells

In clinical cancer research,it is quite promising to develop multimodal synergistic therapeutic strategies.Photodynamic and photothermal synergistic therapy is a very desirable multimodal therapy strategy.Herein,we report a facile and simple method to construct a nanotherapeutic agent for photodynamic and photothermal therapy.This nanotherapeutic agent(ZnO@Ce6-PDA)is composed of a ZnO nanoparticle core,an interlayer of photosensitizer chlorin e6(Ce6)and an outer layer of polydopamine(PDA).Due to the existence of Ce6,the ZnO@Ce6-PDA can efficiently generate singlet oxygen(1O2)under 660 nm laser irradiation.Moreover,the ZnO@Ce6-PDA can serve as a photothermal agent,because of the excellent photothermal conversion efficiency of the PDA coating layer in the presence of 780 nm laser.Experiment results demonstrated that the designed nanotherapeutic agent had outstanding phototoxicity upon the combination of laser irradiation at 660 and 780 nm.Thus,our work proves that the ZnO@Ce6-PDA is a promising photodynamic/photothermal dual-modal nanotherapeutic agent for enhanced cancer therapy.     

Adhesive graphene grown on bioceramics with photothermal property

Recently, graphene has been applied to modify biomaterials due to excellent physicochemical property and biocompatibility. However, some problems still exist especially the weak binding force between graphene and other biomaterials. Herein, a promising platform with photothermal property was constructed by fabricating the adhesive graphene in situ on the surface of β-tricalcium phosphate (β-Ca₃(PO₄)₂, β-TCP) bioceramics using chemical vapor deposition (CVD). The result of ultrasonic cleaning treatment of graphene modified β-TCP (G-TCP) demonstrated that the prepared graphene coating could firmly modified on β-TCP due to the occurrence of carbothermal reduction on the ceramic surface to promote the nucleation and growth of graphene. G-TCP composites exhibited excellent photothermal effects when irradiated with 808 nm near-infrared laser (NIR). The photothermal effect of G-TCP composites could induce more than 90% of osteosarcoma cell (MNNG) death in vitro. These results confirmed that the graphene could be successfully fabricated in situ on the surface of β-TCP by CVD method, and exhibited high firmness and excellent photothermal performance, revealing a promising application in the photothermal therapy of bone tumors.     

铁掺杂的聚2-硝基-1,4-苯二胺纳米球的制备及在光热/光动力/化学动力学肿瘤治疗中的应用

肿瘤微环境(TME)的复杂性,使得单一治疗方式很难实现完全治愈。 为此,构建了一种负载吲哚菁绿(ICG)的铁掺杂的聚2-硝基-1,4-苯二胺多功能纳米球Fe-PNPD-ICG(FPIs),用于光热(PTT)/光动力(PDT)/化学动力学(CDT)的联合治疗。 在808 nm激光器照射下,ICG作为光敏剂可以产生单线态氧,铁掺杂的聚2-硝基-1,4-苯二胺纳米球作为光热剂具有36.65%的光热转换效率。 FPIs一旦内化到肿瘤内,由Fe³⁺/Fe²⁺转化引发Fenton反应产生·OH实现化学动力学治疗,反应过程中可以清除TME中过表达的谷胱甘肽(GSH),从而降低肿瘤中的抗氧化能力。 同时,产生的氧气可以改善TME中乏氧情况,增强PDT的治疗效果。 因此,FPIs是PTT/PDT/CDT联合治疗的一种理想材料,在肿瘤治疗中具有潜在的应用前景。     

LyP-1 peptide-functionalized gold nanoprisms for SERRS imaging and tumor growth suppressing by PTT induced-hyperthermia

The gold nanoprisms (GNPs) have exhibited special plasmonic properties for biomedical applications because of their unique shapes and dimensions. Based on their optical performance, the NIR dye IR780 not only enabled the GNPs-based nanosystem as SERRS nanoparticles for Raman-encoded molecular imaging, but also enhanced the plasmonic photothermal property by laser irradiation. Meanwhile, the GNPs/IR780-Lyp-1 by introduction of tumor-homing peptide segment LyP-1, which presents high affinity to p32 protein, demonstrated the increased enrichment in tumor region and enhanced photothermal therapy efficacy.     

Migration analysis of micro-particles in liquids using microscopically designed external fields.

The recent development of new migration methods of micro-particles in liquids using various external fields is reviewed. The combination of a laser scattering force and a photothermal effect produced photothermal-conversion laser-photophoresis. A dielectric field generated in a planer or a capillary quadrupole electrode realized dielectrophoresis. Using a micrometer-scaled magnetic field gradient, the "Magnetophoretic velocimetry" of micro-particles was invented. Furthermore, the Lorentz force generated by combining an electric field and a magnetic field was utilized for electromagnetophoresis. These new methods were overlooked and the advantages in analytical use were discussed.     

二元混合表面活性剂用于窄吸收金纳米棒的无种子合成

利用十六烷基三甲基溴化铵(CTAB)和油酸钠(NaOL)二元混合表面活性剂体系, 开发了一种高质量金纳米棒(AuNRs)的无种子合成方法. 通过透射电子显微镜(TEM)、 紫外-可见-近红外吸收光谱(UV-Vis-NIR)和热成像仪对金纳米棒的形貌、 光学性质及光热性能进行了表征. 实验结果表明, 当NaOL浓度为8.21~11.5 mmol/L时, 能够获得形貌均匀的AuNRs, 其纵向表面等离子体共振吸收(LSPR)在650~1150 nm范围内可调. 该方法制得的样品具有较窄的LSPR半峰宽, 特别是在制备LSPR在近红外二区(NIR-II, 大于1000 nm)的AuNRs方面具有明显优势. 在1064 nm激光的辐照下, 金纳米棒溶液能够快速升温至67 ℃, 光热转换效率可达31.5%, 同时表现出优秀的光热稳定性, 在近红外二区光声成像和光热治疗方面具有良好的应用价值.     

一种具有光热转换功能的复合薄膜

通过熔融加工和挤出吹塑的方法,制备了反式聚-1,4-异戊二烯(TPI)含量分别为1%、5%和9%的TPI/LLDPE复合薄膜。将复合薄膜置于60℃的饱和碘蒸气中处理,制备得到具有光热转换功能的薄膜。结果表明,复合薄膜中TPI含量越高,经碘蒸气处理后所得薄膜的光热转换能力越强。在功率为0. 9W的激光照射3min后,具有光热转换功能的薄膜表面的温度升高值最大达35℃。