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1.
ATR-FTIR光谱法同时测定香精的相对密度和折光指数   总被引:1,自引:1,他引:0  
傅里叶变换衰减全反射红外光谱 (ATR- FTIR)分析技术与偏最小二乘法 (PL S)相结合 ,建立了香精相对密度、折光指数的校正模型。模型的预测结果与标准方法测定结果在 5 %显著性水平下无显著性差异。该法用于香精物理指标的检测 ,操作简单、快速、准确。  相似文献   

2.
FTIR光谱法与燕窝的品质分析   总被引:16,自引:5,他引:11  
直接采用傅里叶变换红外光谱法(FTIR)获得了30种干燕窝产品的红外光谱图.结果显示,这些谱图与天然燕窝的红外光谱图均有不同程度的差异,主要表现在蛋白质、氨基酸(1 634,1 535 cm-1)和多糖(1 034cm-1)等主要营养成分的吸收峰;在干燕窝的谱图中,亚甲基的吸收峰(2 935 cm-1)及蛋白质和氨基酸的吸收峰(1 647,1 533,1 447 cm-1)等处的峰形、峰位和峰强度均与明胶的谱图较相似,说明大多数干燕窝样品中添加了不同量的明胶等物质;有些干冰糖燕窝产品中冰糖含量高达99%,燕窝仅含1%,在红外谱图上几乎观察不到燕窝的特征蜂.因此,市售燕窝的质量令人担忧.用FTIR可简便、快速、直观的评价燕窝产品的品质.  相似文献   

3.
利用FTIR和漫反射-傅里叶变换红外(DR-FTIR)方法对醋酸乙烯酯(VAc)-二乙烯苯(DVB)共聚微球表面功能化反应进行了研究。结果表明,DR-FTIR光谱比透射FTIR光谱能够获得更多的微球表面信息。  相似文献   

4.
以干燥D-葡萄糖为原料经过乙酰化、端基水解、端基磷酸化、加氢裂解及脱乙酰基4步反应合成了目标产物.产品经FTIR、1H NMR及13C NMR分析确认为α-D-葡萄糖-1-磷酸酯.  相似文献   

5.
合成出了一硫化四甲基秋兰姆(TMTM),采用溶剂蒸发法培养出了单晶TMTM,通过XRD单晶衍射仪、FTIR、TG-DSC对其进行检测和表征,揭示了单晶TMTM的微观结构和内在规律性。XRD单晶衍射从衍射数据、部分健长和键角,揭示TMTM的微观结构,单晶TMTM高度有序化的定向排列结构,决定了其高效的橡胶硫化促进性能。TG-DSC从热效应分析TMTM的性质,FTIR、TG-DSC检测结果表明,单晶TMTM中蕴含很少许的二硫化碳,FTIR揭示了TMTM内部的化学键键型,和单晶衍射仪从不同侧面检测的结果一致,为确定TMTM的分子结构提供了实验依据。TMTM的分解温度偏高,为采用硫化仪研究TMTM的橡胶硫化性能提供参考。本研究为企业选定工作标准品,对TMTM工业化生产进行跟踪检测,评判TMTM的产品性能指标,填报立项TMTM化工行业标准的申报,撰写标准草案,完成国家工业和信息化部的标准制修订项目计划,提供基础实验数据。  相似文献   

6.
矿物药是中国传统药学中不可缺少的重要组成部分。禹余粮作为常用矿物药之一,在临床上有着广泛的使用和确切的疗效,长期用于治疗久泻,便血和崩漏带下。由于禹余粮原矿物成因复杂,通常由多种矿物组成,且组成比例不一,导致目前市场矿物药禹余粮品种来源较混乱,质量参差不齐,真假难以分辨。2010版《中国药典》所收载矿物药禹余粮的质量控制标准仅有简单的性状和铁盐的化学鉴别项目,不能很好的控制禹余粮的质量。通过FTIR方法建立矿物药禹余粮FTIR指纹图谱,并对禹余粮炮制前后及伪品FTIR图谱进行了比较分析。对不同产地和批次18份禹余粮样品进行分析,FTIR指纹图谱相似度评价以计算共有峰透光率的夹角余弦值获得。结果显示,禹余粮样品的FTIR指纹图谱相似度、相关系数均大于0.90;禹余粮生品、炮制品、伪品红外图谱存在较大差异。阐述了利用FTIR指纹图谱研究禹余粮的成分特征,能够快速、简便地区分真伪及炮制前后的禹余粮样品。禹余粮FTIR指纹图谱的建立为矿物药禹余粮质量评价提供了新方法,为《中国药典》禹余粮药材质量标准的完善提供了依据。  相似文献   

7.
利用简便、快速、分辨率高,信息丰富的FTIR,对道地黄芪产地:山西省浑源县官儿乡的6个产地;应县白马石乡的3个产地;繁峙县周庄;内蒙古固阳县的2个产地及其这些产地各4个生长年限生长黄芪的土壤样品(共计42个),进行了较详细的研究,得到了一些有益的结论:黄芪土壤FTIR特征不同于一般土壤;不同产地黄芪土壤的FTIR特征有别,黄芪品质各异;黄芪土壤FTIR特征与党参土壤大不相同;FTIR指纹图谱可以为中药种植的地域选择提供重要信息.  相似文献   

8.
介绍研制的太阳跟踪和傅里叶变换红外(FTIR)光谱技术相结合的大气成分监测系统.该系统跟踪部分以ATmega128芯片为控制核心,结合光学、电子学、GPS模块、PSD位置传感器以及机械部分完成对太阳运行的实时跟踪,利用FTIR光谱仪和计算机处理得到的光谱数据用于大气成分的监测.通过实验验证,FTIR大气成分监测系统运行稳定、可靠,跟踪精度在0.3°以内.  相似文献   

9.
傅里叶变换衰减全反射红外光谱法的应用与进展   总被引:11,自引:0,他引:11  
随着傅里叶变换红外光谱仪的应用及化学计量学的发展 ,傅里叶变换衰减全反射红外光谱法(ATR FTIR)成为用传统透过法制样效果不理想 (或制样复杂 )的样品及表层结构分析的有利工具和手段。ATR FTIR技术已应用到纺织、质检、公安等各个领域。目前 ,人们正在针对ATR FTIR的特性 ,开展应用研究。为此 ,文章主要介绍了国内外应用ATR FTIR技术进行深度剖析的研究 ,对材料表面的定性分析 ,组分的定量分析 ,光学纤维与ATR附件的联用技术 ,以及在其他领域 (如运用ATR FTIR技术考察中空纤维的结构及取向变化 ,研究皮肤促进剂的作用机理 )的研究现状及发展情况  相似文献   

10.
为了探究健康人固体血红蛋白(hemoglobin, Hb)的紫外可见吸收光谱和傅里叶变化红外光谱的谱学特征,将21~80岁健康人分成四个年龄阶段组,采用葡聚糖层析法高度纯化新鲜血液红细胞内的Hb,利用冷冻干燥法获得结构稳定的Hb固体,测定四组样本的Hb紫外可见吸收光谱和FTIR光谱;利用OMNIC 8.0软件的QC比较分析功能、全光谱特征分析和二级结构分析首次归纳得出健康人Hb的紫外光谱及FTIR光谱。分析显示样本间,四组间Hb紫外可见吸收光谱和FTIR光谱高度相同, FTIR光谱间的匹配度高达95%;所有样本Hb的紫外光谱均有5个特征吸收峰,吸收峰所在位置的吸光度、波长相同; FTIR光谱均有13个特征吸收峰,吸收峰所在位置的吸光度、波数是相同的; Hb紫外吸收光谱显示健康人Hb拥有相同的三级结构, FTIR光谱的特征吸收带AmideⅠ带二阶导数谱匹配度高达99%,其二级结构均由11个子峰构成,组成则以α-螺旋为主。研究得出健康人Hb的紫外可见吸收光谱和FTIR光谱,并通过初步分析得到Hb的光谱学特征和结构特点,有助于研究相关疾病。  相似文献   

11.
皮革检测鉴定的市场需求缺口巨大,不同种类皮革,尤其是不同种类真皮革无损、无标记检测具有重要的应用价值。利用太赫兹时域光谱技术系统地测试了不同种类真皮革和人工革的太赫兹透射光谱,计算了不同真皮革和人工革的太赫兹吸收系数和折射率。在0.2~1.5 THz范围内,不同种类皮革的太赫兹吸收系数和折射率数值大小具有明显差异,真皮革大于人工革;且真皮革中,爬行类皮革>鱼类皮革>哺乳类皮革。进一步地,猪、牛、羊真皮革在25~80 ℃加热过程中太赫兹时域光谱振幅变化均在60 ℃左右出现拐点,而人工革无拐点;且猪、牛、羊真皮革变化趋势各异。为了验证皮革太赫兹光谱产生差异的原因,首先对代表性皮革牛皮革、人造革和合成革的主要组成成分牛皮胶原蛋白、聚氯乙烯(PVC)和聚氨酯(PU)进行了太赫兹光谱测试,牛皮胶原蛋白的太赫兹吸收系数和折射率大于聚氯乙烯和聚氨酯;并且在25~80 ℃加热过程中胶原蛋白出现变化拐点,而聚氯乙烯无。实验结果显示,皮革主要组成成分的太赫兹光谱特征的数值差异和变化趋势与对应皮革相同,表明不同种类皮革间差异性的太赫兹光谱特征主要来源于其组成成分的不同。基于此,太赫兹光谱技术有望用于皮革的快速、准确、无损、无标记检测,用于区分不同种类真皮革和人工革,尤其是分辨来源于爬行动物、哺乳动物和鱼类的真皮革。  相似文献   

12.
以新型无铬金属鞣剂鞣制的绵羊皮和猪皮为研究对象,以铬鞣绵羊皮和猪皮为对比。采用微波消解法处理试样,电感耦合等离子体-原子发射光谱法测定主要鞣性金属元素在皮革粒面层、中间层和肉面层的含量。锆在绵羊皮革各层的分布均匀性比猪皮好,正常鞣制皮革中粒面层的含量少于肉面层。钛在绵羊皮革粒面层的含量比例高于锆,在猪皮革粒面层的比例低于锆。绵羊皮革和猪皮革中铬的物质的量总量和各层含量都明显多于锆或钛,铬更容易进入猪皮的粒面层,不易进入中间层。  相似文献   

13.
皮革种类的鉴定对生产控制、贸易过程和市场管理都具有重要意义,目前尚未有皮革种类鉴定的正式检测标准,皮革种类鉴定主要依靠感官法、燃烧法、化学溶解法、显微镜法等综合判定,对人员要求高,主观性强。利用近红外光谱技术对市场五种常见皮革样品(头层牛皮革、剖层移膜革、羊皮革、再生革和人造革)进行分析,利用判别分析法(discriminant analysis,DA)结合标准正态变量变换(multiplicative signal correction,MSC)、多元散射校正(standard normal variate,SNV)、一阶微分(first derivative)、二阶微分(second derivative)等光谱预处理方法进行分类鉴别。结果显示:上述五种革类在同一空间中重叠严重,但是利用样本反面光谱数据可以轻易将人造革和其他革类进行区分,误判率为1.2%,余下四种天然或加工革类重叠稍显严重,在同一个空间内同时对四种革类区分效果不是很理想,两两分组的分类效果较好,误判率13%~17.9%。而不同的数据处理方法在不同的判别分析模型中带来的效果也不尽相同,未发现一种能持续稳定为模型提供优化效果的预处理手段。上述数据说明采用近红外手段对于皮革种类进行判别是具有可行性的,由于本次取样来自于市场上的皮包、皮衣、皮带等最终产品,已经过染色、压花、覆膜等各种复杂处理,可能对模型带来一定的影响,如果能采取一些手段,如扩大样本量等,减弱这些影响,应该能得到更满意的结果。  相似文献   

14.
徐琳 《光谱实验室》2011,28(6):2913-2916
基于红外光谱法可以对不同形态物质进行结构分析,可对皮革产品进行定性分析。依据红外光谱谱带的数目、位置、形状和强度都随化合物不同而各不相同的特点,将牛皮革、羊皮革和聚氯乙烯(PVC)革的红外谱图进行比对和剖析,并用于皮革产品的检验。通过实验得出,利用红外方法可以快速对皮革产品进行红外无损检验。  相似文献   

15.
傅里叶变换衰减全反射红外光谱法鉴定皮革产品   总被引:1,自引:0,他引:1  
徐琳 《光谱实验室》2005,22(6):1274-1276
ATR-FTIR(傅里叶变换衰减全反射红外光谱法)技术分析皮革材料的结构,依据不同物质所得ATR谱的不同,从而快速、简便地分析出真皮革和人造革。该实验技术对样品具有非破坏性,能够准确地对皮革样品进行鉴定。  相似文献   

16.
Influence of ultrasound (US) on various unit operations in leather processing has been studied with the aim to improve the process efficiency, quality, reduce process time and achieve near-zero discharge levels in effluent streams as a cleaner option. Effect of US on substrate (skin/leather) matrix as well as substances used in different unit operations have been studied and found to be useful in the processing. Absorption of US energy by leather in process vessel at different distances from US source has been measured and found to be significant. Effect of particle-size of different substances due to sonication indicates positive influence on the diffusion through the matrix. Our experimental results suggest that US effect is better realized for the cases with pronounced diffusion hindrance. Influence of US on bioprocessing of leather has been studied and found beneficial. Attempts have also been made to improve the US aided processing using external aids. Operating US in pulse mode operation could be useful in order to reduce the electrical energy consumption. Use of US has also been studied in the preparation of leather auxiliaries involving mass-transfer resistance. Preliminary cost analysis carried out for ultrasound-assisted leather-dyeing process indicates scale-up possibility. Therefore, US application provide improvement in process efficiency as well as making cleaner production methods feasible. Hence, overall results suggest that use of US in leather industry is imminent and potential viable option in near future.  相似文献   

17.
以绵羊皮革为研究对象,利用X射线能谱仪(EDXA)分析了鞣性金属锆铬在绵羊皮革中的分布,结果表明:鞣性金属元素锆、铬在绵羊皮革中的分布整体上比较均匀,但局部存在不均匀现象,鞣性金属组分主要分布于纤维束边缘,纤维束的空隙和内部含量均较低.  相似文献   

18.
The effects of ultrasound on titanium tanning of leather were investigated. Either 20 or 40 kHz ultrasound was applied to the titanium tanning of pigskins. Five different treatment conditions were carried out and the effects were examined, such as leather shrinkage temperature (T(s)), titanium content and titanium distribution in the leather. Overall heat loading was carefully controlled. Results showed that 20 kHz ultrasound effectively improves titanium agent penetration into the hide and increases the leather's shrinkage temperature. Doubling the frequency to 40 kHz produced negligible enhancements. An impressive 105.6 degrees C T(s) was achieved using 20 kHz ultrasound pretreatment of the tanning liquor followed by 20 kHz ultrasound in the tanning mixture (liquor plus pigskins) in a special salt-free medium. Finally, using a unique ultrasonic tanning drum with 26.5 kHz ultrasound, the T(s) reached a record level of 106.5 degrees C, a value not achieved in conventional (no ultrasound) titanium tanning. The ultrasonic effects on titanium tanning of leather are judged to make a superior mineral tanned leather.  相似文献   

19.
Nowadays, there is a growing demand for a cleaner, but still effective alternative for production processes like in the leather industry. Ultrasound (US) assisted processing of leather might be promising in this sense. In the present paper, the use of US in the conventional chrome tanning process has been studied at different pH, temperature, tanning time, chrome dose and US exposure time by exposing the skin before tanning and during tanning operation. Both prior exposure of the skin to US and US during tanning improves the chrome uptake and reduces the shrinkage significantly. Prior exposure of the skin to US increase the chrome uptake by 13.8% or reduces the chrome dose from 8% to 5% (% based on skin weight) and shorten the process time by half while US during tanning increases the chrome uptake by 28.5% or reduces the chrome dose from 8% to 4% (half) and the tanning time to one third compared to the control without US. Concomitantly, the resulting leather quality (measured as skin shrinkage) improved from 5.2% to 3.2% shrinkage in the skin exposed to US prior tanning and to 1.3% in the skin exposed to US during the tanning experiment. This study confirms that US chrome tanning is an effective and eco-friendly tanning process which can produce a better quality leather product in a shorter process time with a lower chromium dose.  相似文献   

20.
Studies on the use of power ultrasound in leather dyeing   总被引:12,自引:0,他引:12  
Uses of power ultrasound for acceleration/performing the chemical as well as physical processes are gaining importance. In conventional leather processing, the diffusion of chemicals through the pores of the skin/hide is achieved by the mechanical agitation caused by the paddle or drumming action. In this work, the use of power ultrasound in the dyeing of leather has been studied with the aim to improve the exhaustion of dye for a given processing time, to reduce the dyeing time and to improve the quality of dyed leather. The effect of power ultrasound in the dyeing of full chrome cow crust leather in a stationary condition is compared with dyeing in the absence of ultrasound as a control experiment both in a stationary as well as conventional drumming condition. An ultrasonic cleaner (150 W and 33 kHz) was used for the experiments. Actual power dissipated into the system was calculated from the calorimetric measurement. Experiments were carried out with variation in type of dye, amount of dye offer, temperature and time. The results show that there is a significant improvement in the percentage exhaustion of dye due to the presence of ultrasound, when compared to dyeing in absence of ultrasound. Experiments on equilibrium dye uptake carried out with or without ultrasound suggest that ultrasound help to improve the kinetics of leather dyeing. The results indicate that leathers dyed in presence of ultrasound have higher colour values, better dye penetration and fastness properties compared to control leathers. The physical testing results show that strength properties of the dyed leathers are not affected due to the application of ultrasound under the given process conditions. Apparent diffusion coefficient during the initial stage of dyeing process, both in presence and in absence of ultrasound was calculated. The values show that ultrasound helps in improving the apparent diffusion coefficient more for the difficult dyeing conditions such as in the case of metal-complex dyes having bigger aggregate size compared to less difficult dyeing conditions.  相似文献   

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