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Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 105-115 doi: 10.15302/J-FASE-2019255

摘要:

The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples.

关键词: agro-product     error source     influence factor     near infrared spectroscopy    

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium

Yuheng FENG, Xuguang JIANG, Yong CHI, Xiaodong LI, Hongmei ZHU

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 186-192 doi: 10.1007/s11783-011-0322-6

摘要: In China, safe disposal of hazardous waste is more and more a necessity, urged by rapid economic development. The pyrolysis and combustion characteristics of a residue from producing monopotassium phosphate (monopotassium phosphate residue), considered as a hazardous waste, were studied using a thermogravimetric, coupled with Fourier transform infrared analyzer (TG-FTIR). Both pyrolysis and combustion runs can be subdivided into three stages: drying, thermal decomposition, and final devolatilization. The average weight loss rate during fast thermal decomposition stage in pyrolysis is higher than combustion. Acetic acid, methane, pentane, (acetyl) cyclopropane, 2,4,6-trichlorophenol, CO, and CO were distinguished in the pyrolysis process, while CO was the dominant combustion product.

关键词: hazardous waste     combustion     pyrolysis     thermogravimetric coupled with Fourier transform infrared analysis (TG-FTIR)     monopotassium phosphate residue    

Mechanism study on cellulose pyrolysis using thermogravimetric analysis coupled with infrared spectroscopy

WANG Shurong, LIU Qian, LUO Zhongyang, WEN Lihua, CEN Kefa

《能源前沿(英文)》 2007年 第1卷 第4期   页码 413-419 doi: 10.1007/s11708-007-0060-8

摘要: Based on the investigation of the polysaccharide structure of cellulose by using Fourier transform spectrum analysis, the pyrolysis behaviour of cellulose was studied at a heating rate of 20 K/min by thermogravimetric (TG) analysis

关键词: cellulose     transform     polysaccharide     investigation     TG    

A building unit decomposition model for energy leakage by infrared thermography image analysis

Yan SU, Fangjun HONG, Lianjie SHU

《能源前沿(英文)》 2020年 第14卷 第4期   页码 901-921 doi: 10.1007/s11708-020-0679-y

摘要: A quantitative energy leakage model was developed based on the thermography image data measured for both external and internal building surfaces. The infrared thermography images of both surfaces of doors, windows, and walls of an office building in the Hengqin Campus of University of Macao were taken at various times in a day for four seasons. The transient heat flux for sample units were obtained based on measurements of the seasonal transient local temperature differences and calculations of the effective thermal conductivity from the multiple-layer porous medium conduction model. Effects of construction unit types, orientations, and seasons were quantitatively investigated with unit transient orientation index factors. The corresponding electric energy consumption was calculated based on the air conditioning system coefficient of performance of heat pump and refrigerator cycles for different seasons. The model was validated by comparing to the electric meter records of energy consumption of the air conditioning system. The uncertainties of the predicted total building energy leakage are about 14.7%, 12.8%, 12.4%, and 15.8% for the four seasons, respectively. The differences between the predicted electric consumption and meter values are less than 13.4% and 5.4% for summer and winter, respectively. The typical daily thermal energy leakage value in winter is the highest among the four seasons. However, the daily electric energy consumption by the air conditioning system in summer and autumn is higher than that in winter. The present decomposition model for energy leakage is expected to provide a practical tool for quantitative analysis of energy leakage of buildings.

关键词: heat conductivity     heat coefficient     heat &fllig     ux     infrared thermography     thermal image    

Spontaneous firing properties of rat medial vestibular nucleus neurons in brain slices by infrared visual

XIA Jiao, KONG Weijia, ZHU Yun, ZHOU Yan, ZHANG Yu, GUO Changkai

《医学前沿(英文)》 2008年 第2卷 第3期   页码 264-268 doi: 10.1007/s11684-008-0050-x

摘要: Domestic application of infrared patch clamp techniques on brain slices is limited. The key of the technique is to prepare high-quality brain slices. The present paper describes the preparation procedure of brainstem slices and the spontaneous firing properties of rat medial vestibular nucleus (MVN) neurons. By infrared differential interference contrast technique, neurons of rat MVN were visualized directly at the depth of 50–100 ?m underneath the surface of slices. Firing activities of MVN neurons were recorded by the whole-cell patch clamp technique in artificial cerebrospinal fluid (ACSF) and low Ca - high Mg fluid. The firing mode was more irregular and depressive in low Ca - high Mg fluid than in ACSF. According to the averaged waveform of action potentials, cells were classified as the neurons with monophasic after-hyperpolarization potential (AHP), and the neurons with biphasic AHP. The resting membrane potential (RMP), input resistance (Rin) and membrane capacitance (Cm) of neurons were recorded and compared between groups. With infrared videomicroscopy, patch clamp recordings could be made under direct observation in freshly prepared brainstem slices. The discharge activities of MVN neurons were spontaneous and the firing mode was modulated by extracellular calcium concentration. The basic membrane properties of two types of neurons were not significantly different, while the differences in waveform might play a role in the segregation between tonic and kinetic cells.

关键词: resistance     infrared     infrared videomicroscopy     depressive     after-hyperpolarization potential    

Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm

Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du

《化学科学与工程前沿(英文)》 2019年 第13卷 第3期   页码 599-607 doi: 10.1007/s11705-019-1807-2

摘要: Near-infrared spectroscopy mainly reflects the frequency-doubled and total-frequency absorption information of hydrogen-containing groups (O‒H, C‒H, N‒H, S‒H) in organic molecules for near-infrared lights with different wavelengths, so it is applicable to testing of most raw materials and products in the field of petrochemicals. However, the modeling process needs to collect a large number of laboratory analysis data. There are many oil sources in China, and oil properties change frequently. Modeling of each raw material is not only unfeasible but also will affect its engineering application efficiency. In order to achieve rapid modeling of near-infrared spectroscopy and based on historical data of different crude oils under different detection conditions, this paper discusses about the feasibility of the application of transfer learning algorithm and makes it possible that transfer learning can assist in rapid modeling using certain historical data under similar distributions under a small quantity of new data. In consideration of the requirement of transfer learning for certain similarity of different datasets, a transfer learning method based on local similarity feature selection is proposed. The simulation verification of spectral data of 13 crude oils measured by three different probe detection methods is performed. The effectiveness and application scope of the transfer modeling method under different similarity conditions are analyzed.

关键词: near-infrared spectroscopy     transfer learning     similarity     modeling    

MEMS-based thermoelectric infrared sensors: A review

Dehui XU, Yuelin WANG, Bin XIONG, Tie LI

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 557-566 doi: 10.1007/s11465-017-0441-2

摘要:

In the past decade, micro-electromechanical systems (MEMS)-based thermoelectric infrared (IR) sensors have received considerable attention because of the advances in micromachining technology. This paper presents a review of MEMS-based thermoelectric IR sensors. The first part describes the physics of the device and discusses the figures of merit. The second part discusses the sensing materials, thermal isolation microstructures, absorber designs, and packaging methods for these sensors and provides examples. Moreover, the status of sensor implementation technology is examined from a historical perspective by presenting findings from the early years to the most recent findings.

关键词: thermoelectric infrared sensor     CMOS-MEMS     thermopile     micromachining     wafer-level package    

Design and analysis of electrothermal metasurfaces

Xiu LIU, Zhuo LI, Zexiao WANG, Hyeong Seok YUN, Sheng SHEN

《能源前沿(英文)》 2023年 第17卷 第1期   页码 134-140 doi: 10.1007/s11708-022-0841-9

摘要: Electrothermal metasurfaces have garnered considerable attention owing to their ability to dynamically control thermal infrared radiation. Although previous studies were mainly focused on metasurfaces with infinite unit cells, in practice, the finite-size effect can be a critical design factor for developing thermal metasurfaces with fast response and broad temperature uniformity. Here, we study the thermal metasurfaces consisting of gold nanorods with a finite array size, which can achieve a resonance close to that of the infinite case with only several periods. More importantly, such a small footprint due to the finite array size yields response time down to a nanosecond level. Furthermore, the number of the unit cells in the direction perpendicular to the axis of nanorods is found to be insensitive to the resonance and response time; thus, providing a tunable aspect ratio that can boost the temperature uniformity in the sub-Kelvin level.

关键词: modulated thermal infrared radiation     metasurface     nanosecond response time     sub-Kelvin temperature uniformity     finite size     aspect ratio    

Near-infrared benzodiazoles as small molecule environmentally-sensitive fluorophores

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 128-135 doi: 10.1007/s11705-021-2080-8

摘要: The development of fluorophores emitting in the near-infrared spectral window has gained increased attention given their suitable features for biological imaging. In this work, we have optimised a general and straightforward synthetic approach to prepare a small library of near-infrared-emitting C-bridged nitrobenzodiazoles using commercial precursors. C-bridged benzodiazoles have low molecular weight and neutral character as important features that are not common in most near-infrared dyes. We have investigated their fluorescence response in the presence of a wide array of 60 different biomolecules and identified compound 3i as a potential chemosensor to discriminate between Fe2+ and Fe3+ ions in aqueous media.

关键词: fluorescence     probes     iron     screening     library    

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 216-221 doi: 10.1007/s11783-014-0630-8

摘要: The interaction of the fly ash and NaOH, in an open reflux hydrothermal system at 100°C, has been explored by several researchers and formation of fly ash zeolites has been confirmed based on the X-ray diffraction analysis of the residues. However, this method does not reveal much about the characteristic transitions (viz. elemental, electro-negativity and cation exchange capacity) of the residues. In this situation, resorting to Fourier transform-infrared radiation (FT-IR) spectroscopy on the residues obtained from two-stage hydrothermal treatment process, described in this manuscript, appears to be a novel idea to establish transitions in chemical bonds (viz., -Si-OH-Al-, OH-Na, OH-Al-), crystallinity and cation exchange capacity of these residues. Based on extensive studies, it has been demonstrated that FT-IR spectroscopy is extremely useful for 1) detection of chemical bonds in the residues, 2) evaluation of zeolites in the residues and 3) also establishing the superiority of the two-stage interaction of the fly ash with NaOH for synthesizing better fly ash zeolites (viz., Na-P1 and Hydroxysodalte) as compared to those obtained from the conventional single-stage treatment of the fly ash.

关键词: hydrothermal treatment     alkali activation     fly ash zeolites     X-ray diffraction (XRD) and Fourier transform-infrared radiation (FT-IR) spectroscopy    

Evaluation of automated in-line precision dairy farming technology implementation in three dairy farms in Italy

Maria CARIA, Giuseppe TODDE, Antonio PAZZONA

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 181-187 doi: 10.15302/J-FASE-2019252

摘要:

In recent decades, dairy farms have been exposed to wide variation in profit levels due to a considerable variability of milk price, and energy and feed costs. Consequently, it is necessary for the dairy industry to improve efficiency and productivity by adopting innovative technologies. The automated in-parlour milk analysis and separation is mainly useful to produce low or high quality milk and to monitor the animal health status. Milk with high levels of protein and fat contents may reduce the intensity of standardization during cheesemaking process, reducing production costs. The study aimed to evaluate the efficiency of real-time milk separation during milking and the performance of the milking machine after implementation of AfiMilk MCS. In addition, the economic aspects were assessed. The separation of milk required the existing milking parlors to be equipped with an additional milkline to allow channeling milk with low and high coagulation properties into two different cooling tanks. The results showed that the high coagulation milk fraction, compared to the bulk milk, increased in fat (from 18% to 43%) and protein (from 3% to 7%) concentration. The technology tested has given promising results showing reliability and efficiency in milk separation in real time with affordable implementation costs.

关键词: cheese yield     infrared analysis     milk quality     real-time measurement     sensor    

Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

Subhasis PRADHAN, Shailendra KUMAR, Sudhirkumar V. BARAI

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1561-1572 doi: 10.1007/s11709-020-0640-5

摘要: The physio-chemical changes in concrete mixes due to different coarse aggregate (natural coarse aggregate and recycled coarse aggregate (RCA)) and mix design methods (conventional method and Particle Packing Method (PPM)) are studied using thermogravimetric analysis of the hydrated cement paste. A method is proposed to estimate the degree of hydration ( ) from chemically bound water ( ). The PPM mix designed concrete mixes exhibit lower . Recycled aggregate concrete (RAC) mixes exhibit higher and after 7 d of curing, contrary to that after 28 and 90 d. The chemically bound water at infinite time ( ) of RAC mixes are lower than the respective conventional concrete mixes. The lower , Ca(OH) bound water, free Ca(OH) content and FT-IR analysis substantiate the use of pozzolanic cement in the parent concrete of RCA. The compressive strength of concrete and cannot be correlated for concrete mixes with different aggregate type and mix design method as the present study confirms that the degree of hydration is not the only parameter which governs the macro-mechanical properties of concrete. In this regard, further study on the influence of interfacial transition zone, voids content and aggregate quality on macro-mechanical properties of concrete is needed.

关键词: recycled aggregate concrete     Particle Packing Method     thermogravimetric analysis     chemically bound water     degree of hydration     Fourier transform infrared spectroscopy    

适用于大视场红外地球敏感器的相机标定方法 Research Article

邓华健1,2,王昊1,2,韩晓亚3,刘洋1,2,金仲和1,2

《信息与电子工程前沿(英文)》 2023年 第24卷 第1期   页码 141-153 doi: 10.1631/FITEE.2200079

摘要: 相机的几何精度不足是制约大视场红外地球敏感器精度提升的主要因素。红外地球敏感器相机超大的视场与中心的盲区极大地限制了传统几何标定方法的准确性与可行性。本文提出并验证了一种新型的适用于红外地球敏感器的相机标定方法。三个红外靶标被用作控制点,而相机被安装于双轴转台上。随着转台的旋转,这些控制点将均匀地分布在整个相机视场中。与传统的平行光管与转台配合方法相比,传统方法无法有效覆盖大视场且需要苛刻的实验设备,而该方法更易于实施且成本较低。本文还提出了相应的三步参数估计算法,从而不需要精确测量相机和控制点的位置。本文用10台红外地球敏感器进行了实验,以验证标定方法的有效性。结果表明,所提出的方法是高度稳定可靠的,标定精度与现有其他方法相比提升至少30%。

关键词: 红外地球敏感器;全景红外相机;相机标定    

Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 59-64 doi: 10.1007/s11783-009-0152-y

摘要: Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis, semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process. This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid oil products.

关键词: oil sludge     pyrolysis     Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy (TG-FTIR)     Pyrolysis-Gas Chromatography/Mass Spectrometry (PY-GC/MS)    

Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 41-52 doi: 10.1007/s11705-019-1796-1

摘要: Cyclooxygenase-2 (COX-2) has been used as an excellent traceable biomarker, and exists maximally in Golgi apparatus (Cancer cells). Celecoxib (CCB) is a selective inhibitor for COX-2, and has been used as one of non-steroidal anti-inflammatory drug. Herein we report the conjugation of nile blue (NB) with CCB via a six-carbon linkage to form a fluorescence probe NB-C6-CCB for the detection of COX-2. NB-C6-CCB displays strong fluorescence with the emission peak centered at near-infrared wavelength (700 nm) in tumor cells or tumor tissues with high expression of COX-2. Importantly, NB-C6-CCB can discriminate cancer cells (MCF-7) fluorescence intensity from normal ones (COS-7) in the co-culture medium under confocal microscope. Subcellular localization of the NB-C6-CCB preferentially points to the Golgi apparatus and increases the fluorescent intensity. The competitive analysis (with CCB) and Native-PAGE analysis confirmed that NB-C6-CCB shows selective binding affinity towards COX-2 enzyme. Competitive analysis with CCB (flow cytometry assay) revealed the fluorescence intensity fluctuation due to pretreatment of CCB with different concentrations, indicating that the NB-C6-CCB is a precise or sensitive probe for the COX-2. Tumor tissue (depth: 500 µm), organs and mice imaging tests show excellent near-infrared visualization, specific localization and identification of tumors.

关键词: cyclooxygenase-2     nile blue     CCB     Golgi apparatus     NIR imaging    

标题 作者 时间 类型 操作

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

期刊论文

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium

Yuheng FENG, Xuguang JIANG, Yong CHI, Xiaodong LI, Hongmei ZHU

期刊论文

Mechanism study on cellulose pyrolysis using thermogravimetric analysis coupled with infrared spectroscopy

WANG Shurong, LIU Qian, LUO Zhongyang, WEN Lihua, CEN Kefa

期刊论文

A building unit decomposition model for energy leakage by infrared thermography image analysis

Yan SU, Fangjun HONG, Lianjie SHU

期刊论文

Spontaneous firing properties of rat medial vestibular nucleus neurons in brain slices by infrared visual

XIA Jiao, KONG Weijia, ZHU Yun, ZHOU Yan, ZHANG Yu, GUO Changkai

期刊论文

Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm

Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du

期刊论文

MEMS-based thermoelectric infrared sensors: A review

Dehui XU, Yuelin WANG, Bin XIONG, Tie LI

期刊论文

Design and analysis of electrothermal metasurfaces

Xiu LIU, Zhuo LI, Zexiao WANG, Hyeong Seok YUN, Sheng SHEN

期刊论文

Near-infrared benzodiazoles as small molecule environmentally-sensitive fluorophores

期刊论文

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

期刊论文

Evaluation of automated in-line precision dairy farming technology implementation in three dairy farms in Italy

Maria CARIA, Giuseppe TODDE, Antonio PAZZONA

期刊论文

Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

Subhasis PRADHAN, Shailendra KUMAR, Sudhirkumar V. BARAI

期刊论文

适用于大视场红外地球敏感器的相机标定方法

邓华健1,2,王昊1,2,韩晓亚3,刘洋1,2,金仲和1,2

期刊论文

Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

期刊论文

Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

期刊论文