Study on Methanol Oxidation at Pt and PtRu Electrodes by Combining in situ Infrared Spectroscopy and Differential Electrochemical Mass Spectrometry

Methanol oxidation reaction （MOR） at Pt and Pt electrode surface deposited with various amounts of Ru （denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML） in 0.1 mol/L HClO4＋0.5 mol/L MeOH has been studied under potentiostatic conditions by in situ FTIR spectroscopy in attenuated-total-reflection con guration and di erential electro-chemical mass spectrometry under controlled flow conditions. Results reveal that （i） CO is the only methanol-related adsorbate observed by IR spectroscopy at all the Pt and PtRu electrodes examined at potentials from 0.3 V to 0.6 V （vs. RHE）; （ii） at Pt0.56Ru0.44, two IR bands, one from CO adsorbed at Ru islands and the other from COL at Pt substrate are detected, while at other electrodes, only a single band for COL adsorbed at Pt is observed; （iii） MOR activity decreases in the order of Pt0.73Ru0.27〉Pt0.56Ru0.44〉Pt0.83Ru0.17〉Pt; （iv） at 0.5 V, MOR at Pt0.73Ru0.27 reaches a current e ciency of 50% for CO2 production, the turn-over frequency from CH3OH to CO2 is ca. 0.1 molecule/（site sec）. Suggestions for further improving of PtRu catalysts for MOR are provided.

Application of a novel detection approach based on non-dispersive infrared theory to the in-situ analysis on indicator gases from underground coal fire

Coal mine fires,which can cause heavy casualties,environmental damages and a waste of coal resources,have become a worldwide problem.Aiming at overcoming the drawbacks,such as a low analysis efficiency,poor stability and large monitoring error,of the existing underground coal fire monitoring technology,a novel monitoring system based on non-dispersive infrared(NDIR)spectroscopy is developed.In this study,first,the measurement principle of NDIR sensor,the gas concentration calculation and its temperature compensation algorithms were expounded.Next,taking CO and CH_(4) as examples,the liner correlation coefficients of absorbance and the temperature correction factors of the two indicator gases were calculated,and then the errors of concentration measurement for CO,CO_(2),CH_(4) and C_(2)H_(4) were further analyzed.The results disclose that the designed NDIR sensors can satisfy the requirements of industrial standards for monitoring the indicator gases for coal fire hazards.For the established NDIR-based monitoring system,the NDIRbased spectrum analyzer and its auxiliary equipment boast intrinsically safe and explosion-proof performances and can achieve real-time and in-situ detection of indicator gases when installed close to the coal fire risk area underground.Furthermore,a field application of the NDIR-based monitoring system in a coal mine shows that the NDIR-based spectrum analyzer has a permissible difference from the chromatography in measuring the concentrations of various indicator gases.Besides,the advantages of high accuracy,quick analysis and excellent security of the NDIR-based monitoring system have promoted its application in many coal mines.

Short- and medium-term reproducibility of gastric emptying of a solid meal determined by a low dose of ^(13)C-octanoic acid and nondispersive isotope-selective infrared spectrometry

AIM： To evaluate the reproducibility of a modified 13^C breath test-based measurement of solid phase gastric emptying （GE） within the frames of a simple-repeated measure study protocol. METHODS： Twelve healthy subjects （6 females and 6 males, mean age 24.9＋0.7 years） were recruited to undergo three identical GE examinations. In six subjects the first two examinations were performed 2 d apart, and the third session was carried out at a median interval of 19.5 d （range 18 - 20 d） from the second one. In another six subjects the first two measurements were taken 20 d apart （median, range： 17-23 d）, whereas the third session took place 2 d after the second one. Probes of expiratory air collected before and during six hours after intake of a solid meal （378 kcal） labelled with 75 μL （68 mg） 13^C-octanoic acid, were measured for 13^CO2 enrichment with the nondispersive isotopeselective infrared spectrometry NDIRS apparatus. RESULTS： Taking coefficients of variation for paired examinations into account, the short-term reproducibility of the GE measurement was slightly but not significantly better than the medium-term one： 7.7% and 11.2% for the lag phase （T-Lag）, 7.3% and 10.9% for the gastric half emptying time （T1/2）. The least differences in GE parameters detectable at P= 0.05 level in the 12 paired examinations were 9.6 and 15.6 min for T-Lag, 11.6 and 19.7 min for T1/2 by a two-day or two to three-week time gap, respectively CONCLUSION： The low-cost modification of the breath test involving a lower dose of 13^C-octanoic acid and NDIRS, renders good short- and medium-term reproducibility, as well as sensitivity of the measurement of gastric emptying of solids.

Simultaneous Determination of Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD5) in Wastewater by Near-Infrared Spectrometry

To rapidly determine the pollution extent of wastewater, the calibration models were established for deter-mination of Chemical Oxygen Demand and Biological Oxygen Demand in wastewater by partial least squares and near infrared spectrometry of 120 samples. Spectral data preprocessing and outliers’ diagnosis were also discussed. Correlation coefficients of the models were 0.9542 and 0.9652, and the root mean square error of prediction (RMSEP) were 25.24 mg?L-1 and 12.13 mg?L-1 in the predicted range of 28.40~528.0 mg?L-1 and 16.0~305.2 mg?L-1 for Chemical Oxygen Demand and Biological Oxygen Demand, respectively. By statistical significance test, the results of determination were compared with those of stan-dard methods with no significant difference at 0.05 level. The method has been applied to simultaneous de-termination of Chemical Oxygen Demand and Biological Oxygen Demand in wastewater with satisfactory results.

Structure analysis of optical fiber coupler with infrared spectrometry

To obtain excellent performance optical fiber couplers, the structural difference of SiO2 in couplers with different manufacturing techniques was investigated. With 740-FT-IR infrared spectrometric analyzer, the infrared absorption spectrum of SiO2 in couplers at different drawing velocities was measured, and two characteristic peaks in the wavenumber range of 6502000 cm-1 were observed. One characteristic peak is at about 943 cm-1, which is （attributed） to Si—O—Si bond asymmetric stretching vibration, the other is at about 773 cm-1, which is attributed to （Si—O—Si） bond symmetric stretching vibration. From the infrared spectrum, it is found that the intensity and wavenumber of the characteristic peaks are related to the manufacturing technique of couplers. The characteristic peak at （about） 943 cm-1 becomes steeper when increasing the drawing velocity. At the drawing velocity of 150 μm/s, the distance between the two characteristic peaks is maximum, and then the optical fiber coupler has excellent performance, indicating that the performance of the optical fiber coupler has a close relationship with the wavenumber of the two characteristic peaks.

Study on the Authenticity of Identification Methods in White Spirit by Infrared Spectrometer

This experiment studies on the used infrared spectroscopy to establish technology methods for liquor identification methods, as well as offers the science data for establishment of the fingerprint in white spirit. The results have shown that using near-infrared spectroscopy analysis of liquor has the obvious features such as strong specificity, good reproducibility, simple operation, and finally confirmed that it is an authentic and ideal method for identification in white spirit.

Wireless Low Cost CO₂Monitoring System Design and Evaluation Using Non Dispersive Infrared Sensor

This paper presents a new wireless system for the measurement of CO2 gas concentration for indoor and outdoor purposes based on low cost Non Dispersive Infrared sensors. The system has been implemented on a printed circuit board in order to obtain different aspects of the air pollution. Some experiments were achieved to evaluate the total system combined with an android application on a smartphone. Different tests were realized in a closed room nearly filled with students and also directly while driving on the road. Good results were obtained allowing a future use for air pollution mapping using numerous amounts of sensors inside vehicles.

新吲哚菁绿IR-820辅助的近红外荧光成像和光热及协同治疗在肿瘤诊疗中的应用进展

新吲哚菁绿IR-820因其具有强近红外(near-infrared,NIR,750~1700 nm)荧光特性、良好生物相容性、高光热转换效率及稳定性等优势,在NIR发光的有机荧光染料中脱颖而出,被广泛应用于生物医学成像、荧光标记、细胞实时监测、光热治疗等研究领域。为更好地发挥IR-820的生物医学应用价值,研究人员用不同生物化学分子修饰IR-820来增强其荧光及光热特性,制备多种类的荧光纳米粒子,在基础生物医学成像与肿瘤光热治疗方面开展了众多研究。总结了IR-820荧光纳米粒子在近红外荧光成像和通过光热机理及与其他技术协同治疗肿瘤中的应用研究,希望为进一步推进有机荧光染料IR-820在生物医学领域应用和临床转化发展提供参考。

Extraction of the key infrared radiation temperature features concerning stress and crack evolution of loaded rocks

The infrared radiation temperature(IRT)variation concerning stress and crack evolution of rocks is a critical focus in rock mechanics domain and engineering disaster warning.In this paper,a methodology to extract the key IRT features related to stress and crack evolution of loaded rocks is proposed.Specifically,the wavelet denoising and reconstruction in thermal image sequence(WDRTIS)method is employed to eliminate temporal noise in thermal image sequences.Subsequently,the adaptive partition temperature drift correction(APTDC)method is introduced to alleviate temperature drift.On this basis,the spatial noise correction method based on threshold segmentation and adaptive median filtering(OTSU-AMF)is proposed to extract the key IRT features associated with microcracks of loaded rocks.Following temperature drift correction,IRT provides an estimation of the thermoelastic factor in rocks,typically around 5.29×10^(-5) MPa^(-1) for sandstones.Results reveal that the high-temperature concentrated region in cumulative thermal images of crack evolution(TICE)can elucidate the spatiotemporal evolution of localized damage.Additionally,heat dissipation of crack evolution(HDCE)acquired from TICE quantifies the progressive failure process of rocks.The proposed methodology enhances the reliability of IRT monitoring results and provides an innovative approach for conducting research in rock mechanics and monitoring engineering disasters.

基于NIR和GC-MS融合技术的浓香型白酒原酒等级鉴别

以蒸馏过程中不同等级的浓香型白酒原酒为研究对象,分别获取原酒的近红外光谱(nearinfrared spectroscopy,NIR)数据和气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)数据。采用5点2次卷积平滑对NIR数据进行预处理后,利用竞争性自适应重加权算法(competitive adaptive reweighted sampling,CARS)筛选光谱特征波数;结合Spearman等级相关系数、最大信息系数和随机森林变量重要性筛选GC-MS中影响原酒等级划分的关键风味成分(key flavor components,KC)。然后利用极端梯度提升树分别建立基于NIR和GC-MS以及融合数据的原酒等级鉴别模型。结果表明,基于CARS选择的光谱特征变量建立的模型预测准确率为89.66%,基于特征选择后的KC建立的模型预测准确率为94.83%,基于CARS+KC融合数据建立的模型分类准确率达到了98.28%。研究表明,将GC-MS数据和NIR数据的有效特征信息进行数据融合,可以改善单一检测技术对不同等级原酒特征信息表征不全面的缺点,在单一数据源的基础上提高原酒等级鉴别的准确率和稳定性,实验结果为原酒的等级鉴别以及白酒其他的质量控制提供了新的思路和理论基础。

基于ATR-FTIR及气质联用技术对可可提取物的研究

本研究使用红外光谱技术及GC/MS技术对5种不同类型的可可提取物进行相似度的分析,中国2号可可提取物与英国1号提取物红外光谱相似度达到98.76%,中国1号可可提取物与英国2号可可提取物相似度达到73.43%。5种类型可可提取物共鉴定出48种香气成分,英国1号鉴定出25种,英国2号鉴定出20种,美国1号鉴定出28种,中国1号鉴定出22种,中国2号鉴定出25种。对5种类型可可提取物所鉴定出的香气成分进行主成分分析,可以把中国1号可可提取物与英国2号可可提取物归为一类,把中国2号可可提取物、英国1号可可提取物及美国1号可可提取物归为另一类。通过GC/MS技术结合主成分分析可以对不同类型的可可提取物进行区分,对比传统感官风味评价更具优势,本研究可以为香精产品中原料的替换提供一定的理论依据。

氟诺哌齐结构和性质的密度泛函理论研究

氟诺哌齐是一种新型的抗阿尔茨海默病临床候选药物,目前尚处于临床试验阶段;对氟诺哌齐进行密度泛函理论研究,有助于揭示其分子的性质和功能.在B3LYP/6-311+G(d,p)基组水平上,采用密度泛函理论(DFT)的方法优化氟诺哌齐的分子结构;在相同基组水平下经过谐振频率分析,证实了12种分子构象的稳定结构,并确定了优势构型为DC20-1.根据Marcus理论,对其重组能进行模拟计算,得出氟诺哌齐分子不具备运输性质.通过前线轨道(FMO)分析,发现氟诺哌齐分子具有一定的电子跃迁能力和分子内反应活性,活性反应位点为C15、O28、C23和O26.根据红外光谱、紫外-可见吸收光谱模拟计算结果,对谱图数据进行了讨论分析,研究结果可作为氟诺哌齐表征和鉴别的参考依据.

FT-IR光谱法测定籼米淀粉回生

研究了傅立叶变换红外(FT-IR)光谱法快速检测籼米淀粉回生,发现FT-IR光谱中一些特征振动模式的相对强度(与761.76 cm-1处峰高的比值)会随淀粉回生程度的增加而降低.振动模式包括:3 415 cm-1附近的O—H伸缩振动、2 927.46 cm-1处的CH2伸缩振动、1 155.17 cm-1处C—O和C—C伸缩振动、1 081.89 cm-1处的C—O—H弯曲振动、1 043.32,1 020.18和998.96 cm-1处未确定的振动模式、609.41和578.55 cm-1处的吡喃环骨架振动模式.将以上这些特征振动模式的相对强度倒数与DSC回生焓值进行相关性分析可知:1 081.89,1 043.32,1 020.18,609.41和578.55 cm-1处吸收峰的相关系数均能达到0.9以上,因此可将这5种FT-IR振动模式的相对强度变化作为定量指示淀粉回生程度的多重指标.

硬脂酸亚甲基面外弯曲振动变温FT-IR光谱研究

在293～393 K温度范围内,分别采用傅里叶红外光谱、二阶导数红外光谱、四阶导数红外光谱及去卷积红外光谱测定硬脂酸亚甲基面外弯曲振动(ωCH2),来进一步研究温度对于硬脂酸脂肪链构象的影响。实验发现:在1180～1320cm-1范围内,硬脂酸ωCH2存在"第一特征谱带"和未见文献报道的"第二特征谱带"。硬脂酸脂肪链由全反式有序构象到无序构象的改变的临界温度为353～358K,并进一步研究了温度对于硬脂酸ωCH2红外吸收峰强度的影响。

^1H—NMR和IR对道路沥青老化过程的研究

研究了两种不同结构道路沥青Ｓｈｅｌ７０和ＰＡ１００的老化过程。发现沥青的组成和结构对其老化性能有较大影响：具有较长烷基侧链的道路沥青，在一定的温度下，烷基侧链易于断裂形成自由基而引发氧化反应；沥青各组分结构上的不连续性导致其抗老化性能较差。在老化过程中，由于氧的介入生成了酮和亚砜等含氧官能团，使得沥青分子间相互作用力增加，破坏了原有沥青的组成与结构，导致沥青的针入度下降，各种性质发生明显变化。

FTIR聚类分析结合差热分析法应用于中药材延胡索表征的研究

采用傅里叶变换红外光谱法(FTIR)对不同品种的大叶、小叶延胡索及非正品延胡索进行了直接测定,并用FTIR聚类分析并结合差热分析法(DTA)对延胡索正品的不同品种及与非正品的亲缘关系进行了研究。FTIR聚类分析结果显示5个样品分为4组,大叶、小叶延胡索为一组,齿瓣元胡、东北元胡和土元胡各为一组;差热分析结果显示正品延胡索品种与非正品延胡索的DTA曲线有很明显的区别。所提出方法可有效地鉴别亲缘关系相近的中药材植物。

HJ-1B/IRS热红外数据反演太湖水温的方法比较

太湖是我国典型的富营养化湖泊,水温是影响太湖藻类生长的重要环境因子之一,我国环境减灾卫星HJ-1B搭载的红外多光谱相机IRS对太湖水温动态遥感监测具有较大的性能优势.利用6景过境太湖的IRS热红外遥感影像,分别采用单通道普适性算法、辐射传输模型法和单窗算法反演太湖水温,并与实测水温和同期的TERRA/MODIS温度产品进行对比.结果表明,普适性单通道算法反演水温偏高,而辐射传输模型法和单窗算法则偏低;3种算法反演水温的均方根误差在1.001 K以内,单窗算法反演精度最高,其次是辐射传输模型法,再次为普适性单通道算法,而同期MODIS温度产品的均方根误差为1.507 K.3种算法从IRS热红外数据反演的水温直方图均呈正峰态、尖峰状态分布,反演结果能真实地反映太湖水温的空间分布特征.本研究对只有单个热红外通道的卫星传感器开展内陆水体水温遥感监测具有一定的参考意义.

水/AOT/正庚烷微乳体系中磺酸根水化作用的FT-IR研究

运用傅立叶变换红外光谱（FT－IR）对水／琥珀酸（乙基已基）磺酸钠（AOT）／正庚烷微乳体系中磺酸根的水化作用进行了研究．由于微乳体系中水分子与表面活性剂分子的相互作用，S＝O对称伸缩振动的红外吸收峰向低频方向移动．体系中的加水量W0（水与AOT的摩尔比）由0.5增大至25时，磺酸根对称伸缩振动的红外吸收峰由1051．39cm－1向低频移动至1046．15cm－1．同时，由于Na+的不对称作用，AOT分子中磺酸根反对称伸缩振动分裂成两个吸收峰，分别位于正215cm-1及1245cm－1附近，两个劈裂峰的距离及各自的峰面积均随体系中加水量的变化而变化，应用二阶导数、傅立叶退卷积及曲线拟会等分辨率增强技术可更清楚地反映出这个二重峰的变化情况．固体AOT分子中碳酸根反对称伸缩振动分裂的两个峰之间频率的差值约为42cm－1，形成微乳液以后，这两个峰的差值变小，W0为20时，这两个峰频率的差值逐渐减小到29cm-1。

FRW阻燃中密度纤维板的FTIR分析

采用傅里叶变换红外光谱 (FTIR)法测得FRW阻燃中密度纤维板和未处理普通中密度纤维板的FTIR图谱 ,探讨了FRW阻燃剂与纤维界面间的结合机理。

3种助剂对染色单板耐水色牢度的影响及其FTIR分析

选择3种助剂为助染剂分别添加到浓度一定的酸性大红3R染液中,分别对杨木单板及其综纤维素、木素进行染色处理,测定各助剂对染色单板的耐水色牢度稳定效果,并用红外光谱法对杨木综纤维素、木素各染色试样及3种助剂的浸染试样进行分析。结果表明,3种助剂均能不同程度地提高染色单板的耐水色牢度,其中以双氰胺的效果最好,其次是平平加O—15,最后是纯碱;从FTIR分析可以看出,双氰胺的助染是通过其与染料分子间发生化学结合来实现,而平平加O—15、纯碱则与染料或木材纤维间以物理作用为主。