Vibrational Spectroscopy最新文献

Research on vehicle-mounted measurement of NO2 based on cavity ring-down spectroscopy

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-28 DOI: 10.1016/j.vibspec.2024.103752

Dehao Li , Dan Wang , Yunfei Gao , Jun Duan , Zhiyan Li , Hao Chen , Yuanyuan Qian

Nitrogen dioxide (NO₂) is a significant atmospheric pollutant with notable impacts on the environment and human health. The measurement of NO₂ concentration is crucial for gas phase analysis in atmospheric chemistry, assessment of regional pollution levels, and improvement of data management systems. In this paper, a highly sensitive cavity ring-down spectroscopy (CRDS) technique has been used to measure the concentration of NO₂. The CRDS system utilizes a diode laser and high reflectivity mirrors (over 99.99 %) at 405 nm, achieving a minimum detection limit of 43 ppt (1σ, 40 s) and 92 ppt (1σ, 10 s) as determined by Allan variance. In order to improve the measurement accuracy and stability, the Kalman filtering has been used to process the background ring-down time and ring-down time, and the minimum detection limit can be increased by about 2.06 times to 45 ppt (1σ, 10 s), while preserving temporal response and reducing noise. Under the condition of atmospheric NO₂ measurement, a comparative experiment was carried out in Hefei with the CEAS system. The linear fitting slope was

1.033 \pm 0.017

, and the correlation coefficient reached about 92 %. The CRDS device was integrated for vehicle-mounted measurements of NO₂ concentrations in suburban, urban, and industrial areas of Maanshan City. The experimental result has demonstrated that this system can achieve high-precision, high-sensitivity, and stable measurements of NO₂.

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引用次数: 0

Harnessing the past: Vibration analysis of organic additives in ancient plasters for sustainable building solutions

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-28 DOI: 10.1016/j.vibspec.2024.103751

Bhushan Dhige , Manager Rajdeo Singh

This study investigates plant-based organic additives and grains used in ancient earthen plasters from the caves of Karla, Bhaja, Pitalkhora, Ellora, and Aurangabad in Maharashtra, India, highlighting their relevance for sustainable modern construction. Stereo microscopy, FTIR spectrophotometry, and phytochemical analysis identified rice husk, millet, wheat, Chenopodium album, Paspalum, barnyard millet, foxtail millet, and Fumaria seeds as key organic components. Starch grain analysis confirmed the presence of wheat, millet, and mung bean starches, while polarized light microscopy revealed distinctive birefringence patterns, such as the Maltese cross. FTIR analysis of solvent extractions identified natural compounds, including starches, gums, proteins, oils, waxes, and tree resins. These organic additives, especially rice husk, prevalent in Karla, Bhaja, and Pitalkhora samples, and the balanced composition of hemp fibers, seeds, and gums in Ellora samples, contributed significantly to the strength and durability of the plasters. The use of beeswax and tree resins as natural binders further underscores the ingenuity of these ancient techniques. This research not only highlights the botanical diversity in ancient construction but also draws critical connections to modern sustainable practices. The carbon-negative potential of these materials, combined with their renewability and resilience, aligns closely with contemporary green building strategies, offering inspiration for eco-friendly construction rooted in traditional Indian architecture.

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引用次数: 0

The infrared spectra of primary amides, Part 2. Deuteration of benzamide and hydrogen bonding effects of ortho alkoxybenzamides

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-22 DOI: 10.1016/j.vibspec.2024.103748

T.L. Threlfall , P.N. Threlfall-Holmes , R. Grinter

The wavenumber values in the carbonyl and NH₂ stretching regions of a further 21 amides, all ortho substituted benzamides or heterocyclic carboxamides, are presented. The previous limits on the spectral ranges are thereby widened marginally, but in predictable ways. The NH stretching vibrations of ortho alkoxybenzamides are related to benzamide itself by a curve dependent on intramolecular hydrogen bonding, quantified by further elaboration of the Linnett equations to account for non-equivalence of the two NH bonds. Deuteration experiments enabled uncoupling of the NH bonds and assignment of bond strengths. Although it is widely believed that there is no coupling between XH and XD stretching frequencies, we show that the true NH frequency is raised by 2 cm⁻¹ as a result of deuterium coupling in NHD groups. The calculation of ND₂ wavenumbers from those of the fundamental and first overtone of the NH₂ values was carried out by 4 procedures. Better concordance with the antisymmetric vibration than the symmetric vibration was observed. The calculated shortening of the NH bonds on deuteration is 0.0035±0.0009 Å.

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引用次数: 0

Use of a rugged mid-infrared spectrometer for in situ process analysis of liquids 使用坚固耐用的中红外光谱仪对液体进行现场过程分析

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103747

Catriona McFarlan , Andrew Parrott , Jaclyn Dunn , Jonathon Speed , Dan Wood , Alison Nordon

The widespread application of mid-infrared (MIR) spectroscopy for process monitoring is currently limited by the poor transmission of MIR light through fibre optics. In this work, the performance of a novel and robust MIR spectrometer has been evaluated for practical deployment in a pilot plant or production environment. The spectrometer utilises a Sagnac interferometer design containing no moving parts and is directly attached to an attenuated total reflectance probe, eliminating the need for fibre optics. The quantitative performance of the spectrometer for the in situ analysis of ternary solvent mixtures was assessed. The predictions obtained by partial least squares were accurate (root mean square error of prediction of < 1 % w/w) and comparable to those of a benchmark Michelson-based spectrometer with a fibre-coupled probe, which is more amenable to process development in a laboratory or pilot plant. Calibration transfer between the two spectrometers was performed using the spectral space transformation method to mimic the scenario of the scale-up of a process from the laboratory to pilot scale or from a pilot plant to production scale, where the two different MIR instruments might be deployed. The ability to perform in situ reaction monitoring with the robust Sagnac-based spectrometer was then demonstrated. Spectra acquired during an esterification reaction were resolved using multivariate curve resolution, to produce concentration profiles of each component. These results demonstrate the suitability of this rugged spectrometer for quantitative in situ monitoring of liquid processes, opening up new opportunities for process monitoring in the MIR region.

目前，中红外（MIR）光谱在过程监控中的广泛应用受到了中红外光在光纤中透射率低的限制。在这项工作中，我们对一种新型、坚固耐用的中红外光谱仪的性能进行了评估，以便在试验工厂或生产环境中进行实际部署。该光谱仪采用萨格纳克干涉仪设计，不含移动部件，直接连接到衰减全反射探头上，无需使用光纤。对该光谱仪用于三元溶剂混合物现场分析的定量性能进行了评估。通过偏最小二乘法获得的预测结果准确无误（预测的均方根误差为 1 % w/w），可与带有光纤耦合探头的基准迈克尔逊光谱仪相媲美，后者更适合实验室或中试工厂的工艺开发。两台光谱仪之间的校准转移是通过光谱空间转换方法进行的，以模拟从实验室到中试规模或从中试工厂到生产规模的工艺放大过程，在这种情况下可能会部署两台不同的 MIR 仪器。随后，演示了使用基于萨格纳克的坚固耐用的光谱仪进行现场反应监测的能力。在酯化反应过程中获得的光谱利用多元曲线分辨率进行解析，以生成各组分的浓度曲线。这些结果表明，这种坚固耐用的光谱仪适用于对液体过程进行定量原位监测，为中红外区域的过程监测带来了新的机遇。

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引用次数: 0

Trace level detection of the azo base of organic dye by surface-enhanced Raman spectroscopy

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103750

Geraldine Jara , Rodrigo Sánchez-González , Camila F. Olguín , Carolina P. Candia , Jorge Pavez , Carlos P. Silva , Elizabeth Imbarack

Water pollution with synthetic pigments is becoming an emerging problem due to the potential damage to aquatic sources and its consequences for flora, fauna, and human health. Currently, techniques to detect the presence of these pollutant pigments in water reach concentrations of µg/L and require pretreatment to detect them. In this work, we present a quick and easy methodology to determine the presence of the basic unit used in textile pigments, 4-(pyridin-4-yldiazenyl)phenyl-amine (4-PDPA), in a synthetic seawater matrix and a real one from the coast of the city of Valparaíso, Chile, using Surface Enhanced Raman Spectroscopy (SERS). Colloidal gold was used as the active surface, spectra corresponding to the pigment profile were recorded without pretreatment of the matrix used, and the pigment was detected at concentrations 0.00198 µg/L up to two orders of magnitude lower than current methods (0.0198 µg/L).

引用次数: 0

Evaluating the thermal stability of hazelnut oil in comparison with common edible oils in Turkey using ATR infrared spectroscopy 使用 ATR 红外光谱法评估榛子油与土耳其常见食用油的热稳定性比较

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103743

Gulgun Cakmak-Arslan , Kubra Gulsen

Hazelnut oil (HO), a high-quality nutrient rich in monounsaturated fatty acids and antioxidants, is not commonly used due to a lack of awareness of its nutritional benefits. The purpose of the current study is to evaluate the stability of HO during the heating process in comparison with Riviera olive, sunflower and corn oils, the most commonly used edible oils in Turkey, by using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR). The oils were heated at 180 °C for 24 h, divided into 8-h periods over the course of three days and the measurements were performed on oil samples taken every 2 h. Thermogravimetric analysis-differential thermal analysis (TGA-DTA) and the measurement of the specific absorbance of conjugated dienes and trienes by using UV–visible spectroscopy were also performed to confirm the ATR-FTIR data. The spectroscopic results showed that the heating process led to an increase in the amount of primary and secondary oxidation products, a decrease in the amount of cis fatty acids and an increase in the amount of trans fatty acids in all oils. Based on the results of linear regression analysis, HO has the lowest slope value for all parameters, indicating that it is the most resistant to thermal oxidation. Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA) and TGA-DTA results confirmed that HO has a higher thermal stability than the other oils. These findings revealed that HO has the highest thermal stability among the oils compared and can be utilized as a healthy alternative for cooking. This study also showed that ATR-FTIR spectroscopy holds significant promise in oil analysis, competing with routine quality control techniques.

榛子油（HO）是一种富含单不饱和脂肪酸和抗氧化剂的优质营养物质，但由于人们对其营养价值缺乏了解，因此并不常用。本研究的目的是通过使用衰减全反射-傅立叶变换红外光谱（ATR-FTIR），将榛子油与里维埃拉橄榄油、葵花籽油和玉米油（土耳其最常用的食用油）进行比较，评估榛子油在加热过程中的稳定性。这些油在 180 °C 下加热 24 小时，每 8 小时加热一次，共加热三天，每隔 2 小时对油样进行一次测量。为了证实 ATR-FTIR 数据，还进行了热重分析-差热分析（TGA-DTA）以及利用紫外可见光谱测量共轭二烯和三烯的比吸收率。光谱结果表明，加热过程导致所有油类中初级和次级氧化产物的数量增加，顺式脂肪酸的数量减少，反式脂肪酸的数量增加。根据线性回归分析的结果，HO 在所有参数中的斜率值最低，表明其抗热氧化能力最强。主成分分析（PCA）、层次聚类分析（HCA）和 TGA-DTA 结果证实，HO 的热稳定性高于其他油类。这些研究结果表明，在所比较的油类中，HO 的热稳定性最高，可用作烹饪的健康替代品。这项研究还表明，ATR-傅立叶变换红外光谱技术在油类分析中大有可为，可与常规质量控制技术相媲美。

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引用次数: 0

New insights of emerald geographic origin determination based on the infrared spectroscopy of D2O and HDO molecules 基于 D2O 和 HDO 分子红外光谱测定祖母绿地理产地的新见解

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103746

Yu-Yu Zheng , Xiao-Yan Yu , Bo Xu , Hong-Shu Guo , Si-Yi Zhao , Jun Tang , Ying Yan , Yu-Jie Gao

Emerald geographic origin determination in laboratories typically relies on the microscopic features of inclusions, ultraviolet through visible and near-infrared (UV-Vis-NIR) spectroscopy, and trace element chemistry measured by laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS). Infrared (IR) spectroscopy, a non-destructive technique, has played a minor role in this process. This work conducts a systematic examination of emerald samples from twelve origins, encompassing spectroscopic, and trace element analyses. For the first time, IR absorptions related to D₂O and HDO molecules within the 2600–2850 cm^–1 range from multiple origins (333 emerald samples) were recorded, assigned, and classified. These IR absorptions, controlled by the concentrations of deuterium (D) and alkali metals (primarily sodium) within channels, reveal three distinct patterns and derived four groups that serve as strong evidence for origin determination. Emeralds from Zambia group display the most prevalent HDO-dominant IR-pattern I characterized by the pronounced absorption peak of Type II HDO at 2672 cm^–1; Panjshir (Afghanistan) and Swat (Pakistan) emeralds exhibit the transitional type IR-Pattern II with overall five peaks and obvious 2808 cm^–1 peak; D₂O-dominant IR-Pattern III is featured by marked absorption band at 2740 cm^–1, and can be further subdivided into two subtypes (IIIa and IIIb). IR-Pattern IIIb is currently only found in Nigerian emeralds, characterized by strong broad band of Type I D₂O due to enriched deuterium and obvious absorption of Type I HDO at 2685 cm^–1 due to depleted sodium. Furthermore, this research updates the classification of UV-Vis-NIR spectra, unveils the trace element features, and presents effective compositional diagrams. This contribution enriches and expands existing techniques and provides new insights for emerald origin determination.

在实验室中确定祖母绿的地理产地，通常依靠内含物的显微特征、紫外-可见光和近红外（UV-Vis-NIR）光谱以及通过激光烧蚀-电感耦合等离子体质谱法（LA-ICP-MS）测量的微量元素化学成分。红外（IR）光谱作为一种非破坏性技术，在这一过程中发挥了次要作用。这项工作对 12 个产地的祖母绿样本进行了系统检测，包括光谱和痕量元素分析。首次对来自多个产地（333 个翡翠样品）的 2600-2850 cm-1 范围内与 D2O 和 HDO 分子相关的红外吸收进行了记录、分配和分类。这些红外吸收受通道内氘（D）和碱金属（主要是钠）浓度的控制，显示出三种截然不同的模式，并衍生出四个组别，作为确定产地的有力证据。赞比亚组的祖母绿显示出最普遍的 HDO 主导型红外模式 I，其特征是在 2672 厘米-1 处有明显的 II 型 HDO 吸收峰；潘杰希尔（阿富汗）和斯瓦特（巴基斯坦）的祖母绿显示出过渡型红外模式 II，共有五个峰和明显的 2808 厘米-1 峰；D2O 主导型红外模式 III 的特征是在 2740 厘米-1 处有明显的吸收带，并可进一步细分为两个亚型（IIIa 和 IIIb）。目前，IR-Pattern IIIb 仅存在于尼日利亚祖母绿中，其特征是富氘导致的 I 型 D2O 强烈宽带和贫钠导致的 I 型 HDO 在 2685 cm-1 处的明显吸收。此外，这项研究还更新了紫外-可见-近红外光谱的分类，揭示了微量元素的特征，并提出了有效的成分图。这一贡献丰富和扩展了现有技术，为确定祖母绿产地提供了新的见解。

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引用次数: 0

Preparation and characterization of 5-fluorouracil drug cocrystal and its dynamic monitoring of cocrystallization process via SERS spectroscopy 5- 氟尿嘧啶药物共晶体的制备和表征及其通过 SERS 光谱对共晶体化过程的动态监测

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103749

Fan Yang , Jing Zhao , Zhengang Wu , Yingna Wei , Hengyong Wei , Jingwu Li , Bo Li

Cocrystal is a new class of pharmaceutical crystal form, which could improve the physical and chemical properties of drug substance without affecting the internal structure of drug substance. Therefore, the cocrystals show a great deal of potential in the development and research of drugs. 5-Fluorouracil (5-FU) is one of the most widely used anti-pyrimidine drugs. However, its solubility is poor and its oral bioavailability is low. In this work, the cocrystal of 5-FU with nicotinamide was prepared by the solvent evaporation method. The cocrystal structure was confirmed by infrared spectroscopy (IR), X-ray diffraction (XRD) and Raman spectroscopy. The X-ray diffraction and infrared spectroscopy presented that there were significantly different peaks between the raw drug and the cocrystal. Raman spectral results also indicated the differences of such cocrystal compared with the raw drug. In addition, TiN-Ag composite SERS substrate was used to study the formation of 5-FU cocrystal drugs and the formation process was dynamically monitored, and the interaction between molecules during the cocrystal reaction was deeply understood. The cocrystal reaction process was tracked, it can be found that the peak intensity of the raw drug and cocrystal changes with the reaction, indicating that the TiN-Ag composite substrate can monitor the cocrystal transformation process.

共晶体是一类新的药物晶体形态，它可以在不影响药物内部结构的前提下改善药物的物理和化学性质。因此，茧晶在药物的开发和研究中显示出巨大的潜力。5-氟尿嘧啶（5-FU）是应用最广泛的抗嘧啶药物之一。然而，其溶解性较差，口服生物利用度较低。本研究采用溶剂蒸发法制备了 5-FU 与烟酰胺的共晶体。通过红外光谱（IR）、X 射线衍射（XRD）和拉曼光谱证实了该共晶体的结构。X 射线衍射和红外光谱显示，原药和共晶体的峰值明显不同。拉曼光谱结果也表明这种共晶体与原药相比存在差异。此外，还利用 TiN-Ag 复合 SERS 基底研究了 5-FU 药物共晶体的形成，并对形成过程进行了动态监测，深入了解了共晶体反应过程中分子间的相互作用。通过对共晶体反应过程的跟踪，可以发现原药和共晶体的峰值强度随着反应的进行而变化，这表明 TiN-Ag 复合基底可以监测共晶体的转化过程。

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引用次数: 0

Diagnosis of corn leaf diseases by FTIR spectroscopy combined with machine learning 傅立叶变换红外光谱与机器学习相结合诊断玉米叶片病害

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103744

Qinru Ni , Yehao Zuo , Zhaoxing Zhi , Youming Shi , Gang Liu , Quanhong Ou

Corn is among the world's most vital crops, yet its yield and quality are often compromised by leaf diseases. Timely and accurate detection of such diseases is thus crucial. In this study, Fourier-transform infrared (FTIR) spectra (4000–400 cm⁻¹) were obtained for leaves afflicted by northern corn leaf blight (NCLB) and gray leaf spot (GLS), alongside spectra from healthy corn leaves as controls. Various machine learning-based classification models were then developed to facilitate precise disease diagnosis. To reduce redundancy and extract pertinent spectral information, the variable importance projection (VIP) algorithm and random leapfrog (RF) method were employed for feature selection. The resulting spectral features were subsequently used as inputs for the classification models. Of the twelve models evaluated, the VIP-KNN model demonstrated the most exceptional performance. While the original FTIR spectrum comprised 1867 data points, the VIP-KNN model achieved classification using only 615 critical data points, delivering an accuracy of 97.46 %, sensitivity of 96.08 %, and precision of 95.96 %. This highlights how the feature selection approach mitigated overfitting and substantially enhanced the model's classification accuracy. The findings of this research underscore the potential of combining FTIR spectroscopy with machine learning for the effective diagnosis of corn leaf diseases, the accuracy of this detection method is high, and the average accuracy of the model is as high as 93.41 %.

玉米是世界上最重要的农作物之一，但其产量和质量却常常受到叶片病害的影响。因此，及时准确地检测此类病害至关重要。在这项研究中，获得了受北方玉米叶枯病（NCLB）和灰色叶斑病（GLS）影响的叶片的傅立叶变换红外（FTIR）光谱（4000-400 cm-¹），以及作为对照的健康玉米叶片的光谱。然后开发了各种基于机器学习的分类模型，以便进行精确的疾病诊断。为减少冗余并提取相关光谱信息，采用了可变重要性投影（VIP）算法和随机跃迁（RF）方法进行特征选择。由此产生的光谱特征随后被用作分类模型的输入。在评估的 12 个模型中，VIP-KNN 模型表现最为出色。原始傅立叶变换红外光谱包含 1867 个数据点，而 VIP-KNN 模型仅使用 615 个关键数据点就实现了分类，准确率达 97.46%，灵敏度达 96.08%，精确度达 95.96%。这凸显了特征选择方法如何减轻了过拟合，并大大提高了模型的分类准确性。这项研究的结果凸显了傅立叶红外光谱与机器学习相结合有效诊断玉米叶片病害的潜力，这种检测方法的准确率很高，模型的平均准确率高达 93.41 %。

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引用次数: 0

Discovery of calcium sulfate at different hydration states on Mars - based on perseverance SHERLOC analysis 基于坚持不懈的 SHERLOC 分析，在火星上发现不同水合状态的硫酸钙

IF 2.7 3区化学 Q2 CHEMISTRY, ANALYTICAL

Vibrational Spectroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.vibspec.2024.103745

Yian Wang , Peipei Fang , Hongpeng Wang , Yingjian Xin , Xinru Yan , Mingkang Duan , Zhiping He , Xiong Wan

Organic matter on planets is often co-deposited with evaporites, and evaporation of lakes in the Jezero region of Mars may have led to the deposition of abundant organic matter and minerals such as sulfates, making sulfates important minerals for preserving the remains of potential life on Mars, especially in different hydration states, will help to invert the variability of the Martian environment and provide guidance for the exploration of life on Mars. Raman spectroscopy can detect the molecular composition of organic matter and acid anion information of the target of interest, thus enabling in situ analysis of life information and its living environment. In order to realize the detection of life remains on Mars, The Perseverance rover is equipped with SHERLOC in situ material detection payload, which adopts a 248.6 nm deep ultraviolet (DUV) laser to simultaneously excite Raman and fluorescence signals of the target. In this paper, five scans in three modes (survey scan, HDR scan and detail scan) from two sites on Mars (Quartier and Bellegarde) were selected for preliminary analysis, and the presence of sulfate minerals at these two sites was confirmed. The detail scans at Quartier were analyzed in depth, and the presence of four calcium sulfate minerals, gypsum (CaSO₄∙2 H₂O), bassanite (CaSO₄∙0.5 H₂O), anhydrite (β-CaSO₄) and gamma-calcium sulfate (γ-CaSO₄)was inferred from the states of ν₁ (SO₄), ν₃ (SO₄) and hydrated peaks. The differences in the degree of hydration of calcium sulfate minerals suggest that there may have been active water activity on Mars. By comparing data collected by SHERLOC with spectra from spectral libraries, the composition of small-scale structures on Mars may be assessable. However, due to the complexity of the Martian geology, more accurate water activity will need to be combined with more detailed ions, temperatures, humidity, and other conditions for a more precise analysis.

行星上的有机物往往与蒸发岩共同沉积，火星杰泽罗地区湖泊的蒸发可能导致了丰富的有机物和硫酸盐等矿物质的沉积，硫酸盐成为保存火星潜在生命遗迹的重要矿物质，尤其是不同水合状态下的硫酸盐，将有助于反演火星环境的变异性，为火星生命探索提供指导。拉曼光谱可以探测相关目标的有机物分子组成和酸阴离子信息，从而实现对生命信息及其生存环境的原位分析。为了实现对火星上生命遗迹的探测，"坚毅 "号探测器配备了SHERLOC原位物质探测有效载荷，它采用248.6 nm深紫外（DUV）激光同时激发目标的拉曼和荧光信号。本文选取了火星上的两个地点（Quartier 和 Bellegarde）的三种模式（勘测扫描、HDR 扫描和细节扫描）的五次扫描进行初步分析，并确认了这两个地点存在硫酸盐矿物。对 Quartier 的详细扫描进行了深入分析，并根据 ν1 (SO4)、ν3 (SO4) 和水合峰的状态推断出存在四种硫酸钙矿物，即石膏（CaSO4∙2 H2O）、重晶石（CaSO4∙0.5 H2O）、无水石膏（β-CaSO4）和伽马硫酸钙（γ-CaSO4）。硫酸钙矿物水化程度的差异表明，火星上可能存在活跃的水活动。通过将 SHERLOC 收集到的数据与光谱库中的光谱进行比较，可以评估火星上小规模结构的组成。然而，由于火星地质的复杂性，更精确的水活动需要与更详细的离子、温度、湿度和其他条件相结合，才能进行更精确的分析。

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引用次数: 0