Detection and Classification of Honey Adulteration Combined with Multivariate Analysis

Honey is a natural sweetener with a yellowish substance made up of bee secretions and plant nectar extracts. Main composition of honey are sugars or carbohydrates and water in the chemical composition and contain a great number of minor components such as minerals, amino acids, proteins, acidity, and pH. Honey adulteration is a global concern due to lack of awareness of people and policies. There is a various method that has been conducted to detect honey adulteration such as SCIRA, DSC, FTIR, NIRS, and NMR and these methods mostly used multivariate data analysis to classify the adulteration of honey. PCA is the most used technique in the classification of honey adulteration where the data obtained is clustered according to adulteration level and type of the adulterant. This paper explains on different methods to detect honey adulteration and common technique used on classification of honey. It can be concluded that PCA is the most used technique based on different method of honey adulteration detection

a perspective on materials, synthesis methods and applications

The oxides of copper (CuxO) are fascinating materials due to their remarkable optical, electrical, thermal and magnetic properties. Nanostructuring of CuxO can further enhance the performance of this important functional material and provide it with unique properties that do not exist in its bulk form. Three distinctly different phases of CuxO, mainly CuO, Cu2O and Cu4O3, can be prepared by numerous synthesis techniques including, vapour deposition and liquid phase chemical methods. In this article, we present a review of nanostructured CuxO focusing on their material properties, methods of synthesis and an overview of various applications that have been associated with nanostructured CuxO

Preliminary Study of pH Sensor for Engine Oil Deterioration Detection Using Anodized Ta2O5 Nanotubular

pH sensor is one of the sensing principles that can be employed in detection of engine oil deterioration. To avoid unnecessary changing of engine oil while maintaining the oil quality consumed by car’s engine, engine oil deterioration sensor is required to continuously monitor the oil condition. In this work, we fabricated pH sensor sensing layer made up of tantalum thin film. Ta2O5 nanotubular was constructed as the medium of interaction to measure the quality of engine oil. Anodization synthesis method was used to fabricate the sensing layer by varying the anodization time. Two samples anodized at 30 min and 60 min were tested in pH buffer solution at pH ranging from 2, 4, 7, 10 and 12. Further characterization using field emission scanning electron microscope (FESEM) was conducted to investigate the surface morphology properties, while X-ray diffraction (XRD) was conducted to obtain crystal properties of Ta2O5 nanotubular. A homogeneous Ta2O5 nanostructures with cubic crystal structure and pore diameter ranging between 15 to 20 nm was obtained. 30 min sample tested in pH buffer solution has better adsorption of H+ ions with linear pH sensitivity of 31.616 mV/pH and good stability. Therefore, anodization method can be an alternative to fabricate pH sensor for oil deterioration detection system. Additionally, other study on chemical sensor for the detection of engine oil deterioration level are also discussed in this paper

Low-temperature-dependent growth of titanium dioxide nanorod arrays in an improved aqueous chemical growth method for photoelectrochemical ultraviolet sensing

The growth of titanium dioxide nanorod arrays (TNAs) in aqueous solutions containing titanium butoxide and hydrochloric acid can be controlled by regulating the temperature from 115 to 150 °C as an adjustable physical parameter. The transparent colloidal solution of titanates is clouded on the basic growth of TNAs when heated at a certain temperature using an improved aqueous chemical growth method in a clamped Schott bottle. The structural, optical and electrical properties of grown TNAs films were thoroughly investigated and discussed. The distinct and high-intensity peaks observed in the X-ray diffraction pattern and Raman spectra of the grown TNAs show the rutile phase with high crystal quality. The crystallite size, diameter size, and thickness of TNAs decrease with decreasing growth temperature. The prepared TNAs were used to detect 365 nm ultraviolet (UV) photon energy (750 µW/cm2) in a photoelectrochemical cell structure with a maximum photocurrent of 26.31 µA and minimum photocurrent of 3.48 µA recorded for TNAs grown at 150 °C and 115 °C, respectively. The size, structural properties, charge transfer resistance, and electron lifetime play a key role in determining the UV sensing characteristics of the TNAs. Results show that TNAs are very promising in fabricating a UV sensor with a high response at 0 V bias even at a low growth temperature of 115 °C

The properties of sonicated immersion grown hematite films at various annealing temperatures

In this research, hematite (α-Fe2O3) film was synthesized to study the effect of annealing temperature on its crystallinity, optical and electrical properties. Through a sonicated solution immersion technique, hematite films were deposited on a fluorine-doped tin oxide (FTO) glass substrate. In the synthesis process, 0.2 M ferric chloride (FeCl3·6H2O) was used as a precursor, 0.2 M urea (NH2CONH2) as the stabilizer, and de-ionized (DI) water as a solvent to produce 200 ml of aqueous solution. During the annealing treatment, we varied the temperatures at 350 ºC, 450 ºC and 500 ºC. The X-ray diffraction (XRD) pattern revealed the presence of peaks of 2θ angles between 20° to 90°, corresponding to (104), (110), (214), (125) and (128) planes, which exhibited crystalline structures of rhombohedral with diffraction peaks of hematite phase (α-Fe2O3). Optical characterizations showed that the transmittances of all samples were close to 100% in the high wavelength level of the visible light region, which is close to the infrared spectrum. Absorption of hematite samples was found to be more than 0.6 a.u. in the low wavelength level of the visible light region close to the ultraviolet spectrum and close to 0 in the high wavelength level of the visible light region close to the infrared spectrum. A sample with an annealing temperature of 500 °C has the lowest transmission and the highest absorbance in the visible region due to dim pigments in the hematite film

FT-NIR, MicroNIR and LED-MicroNIR for detection of adulteration in palm oil via PLS and LDA

Chemometrics analysis was performed to compare the performance of FT-NIR, MicroNIR and LED-NIR for detection of adulteration in palm oil. FT-NIR has a high spectral resolution and signal-to-noise ratio, but MicroNIR is more light weight and suitable for on-site application. The feasibility of LED to replace the conventional halogen tungsten light source in MicroNIR has been discussed in this paper. The wavelength of LEDs was based on the variable selection method, CARS, and the results were in good agreement with the C–H and O–H bond interaction displayed in the observed NIR spectrum. The advantages of using LED instead of a halogen tungsten light source are cost effectiveness, low power consumption and reduced number of variables. Different pretreatment approaches has been applied to the spectral data acquired to investigate the performance of preprocess to the result of chemometrics. Quantitative analysis was performed using partial least square (PLS) algorithms with the linear regression method. The best correlation coefficient, (R2), reported using FT-NIR was 0.99 with RMSEC and RMSEP values less than 1, indicating that the spread of calibration and prediction data was small. The LDA result showed that LED-NIR outperforms FT-NIR and MicroNIR with a sensitivity of 1.00 and a specificity of 0.9333

Annealing effect on ultraviolet sensor performance with porous silicon based

Nowadays, most semiconductor industries apply silicon-based material in developing advanced electronic device. Concerns with heat management of electronic devices which getting worst day by day, the nanostructures technologies were introduced in order to overcome the problem. The nanostructures development on bulk crystalline silicon known as porous silicon which could be produced via anodization method. In this study, the anodized porous silicon was annealed at temperatures of 200°C up to 800°C for the research purpose of annealing effect on ultraviolet sensor performance. The structures of porous silicon were analyzed via FESEM and XRD characterization in order to identify the morphology and crystallinity of porous silicon. Then, the ultraviolet sensors were produced and the sensors performance were analyzed. After post-annealing treatment, the anodized porous silicon has the strongest crystalline peak at 600°C and 800°C, while below 400°C, the porous silicon samples have a broadened XRD peak around 2 θ=33°. However, our experimental results show that an ultraviolet sensor which anneal at temperature 200°C have the best sensing performance

Coupling heterostructure of thickness-controlled nickel oxidenanosheets layer and titanium dioxide nanorod arrays via immersionroute for self-powered solid-state ultraviolet photosensor applications

A coupling heterostructure consisting of nickel oxide nanosheets (NNS) and titanium dioxide nanorod arrays (TNAs) was fabricated for self-powered solid-state ultraviolet (UV) photosensor applications. By controlling the thickness of the NNS layer by via varying the growth time from 1 to 5 h at a deposition temperature of 90 °C, the coupling NNS/TNAs heterojunction films were formed and their structural, optical, electrical and UV photoresponse properties were investigated. The photocurrent measured from the fabricated self-powered UV photosensor was improved by increasing the thickness of NNS from 140 to 170 nm under UV irradiation (365 nm, 750 µWcm−2) at 0 V bias. A maximum photocurrent density of 0.510 µA∙cm−2 was achieved for a sample with a NNS thickness of 170 nm and prepared with a 3 h NNS growth time. Our results showed that the fabricated NNS/TNAs heterojunction has potential applications for self-powered UV photosensors

Thin films and nanostructures of niobium pentoxide: fundamental properties, synthesis methods and applications

As one of the transition metal oxides, niobium pentoxide (Nb2O5) offers a broad variety of properties that make it a potentially useful and highly applicable material in many different areas. In comparison to many other transition metal oxides, Nb2O5 has received relatively little attention, which presents a significant opportunity for future investigations aimed at fundamentally understanding this material and finding new and interesting applications for it. In this article, a general overview of Nb2O5 is presented which focuses on its fundamental properties, synthesis methods and recent applications, along with a discussion on future research directions relevant to this material

Detection and Classification of Honey Adulteration Combined with Multivariate Analysis

Honey is a natural sweetener with a yellowish substance made up of bee secretions and plant nectar extracts. Main composition of honey are sugars or carbohydrates and water in the chemical composition and contain a great number of minor components such as minerals, amino acids, proteins, acidity, and pH. Honey adulteration is a global concern due to lack of awareness of people and policies. There is a various method that has been conducted to detect honey adulteration such as SCIRA, DSC, FTIR, NIRS, and NMR and these methods mostly used multivariate data analysis to classify the adulteration of honey. PCA is the most used technique in the classification of honey adulteration where the data obtained is clustered according to adulteration level and type of the adulterant. This paper explains on different methods to detect honey adulteration and common technique used on classification of honey. It can be concluded that PCA is the most used technique based on different method of honey adulteration detection