Arsenic is a toxic element. Chronic exposure to arsenic can pose a variety of health problems including cancers, lung disease, skin lesions, diabetes, gangrene, reproductive disorders, hypertension, and heart disease....Arsenic is a toxic element. Chronic exposure to arsenic can pose a variety of health problems including cancers, lung disease, skin lesions, diabetes, gangrene, reproductive disorders, hypertension, and heart disease. Globally the concern of arsenic is growing day by day. Addressing this concern, the study aimed to assess the arsenic level in raw rice grain and rice cooked with tubewell water and rainwater. The study was conducted at the Sholotaka Union of Gangni Upazila in Meherpur District of Khulna Division, Bangladesh in 2023. For this purpose, seven raw samples including rice grain, rainwater and tubewell water samples and six cooked rice samples were analyzed. Rice and water samples were digested using the USEPA method-3050B in Arsenic Center Jashore, under Asia Arsenic Network, Japan. The arsenic level in the samples was tested using the HG-AAS method using a Shimadzu model AA7000 (Japan) Atomic Absorption Spectrophotometer. The study’s findings revealed that arsenic concentration in rainwater samples consistently displays 0 mg/l indicating the absence of arsenic in this sample. Three (03) tube well water samples and three (03) raw rice grain samples showed a significant variation in arsenic concentration. The mean value of tubewell water samples T1, T2, and T3 was found 0.53 ± 0.003 mg/l, 0.31 ± 0.003 mg/l, and 0.65 ± 0.002 mg/l, respectively. Whereas raw rice grain samples RG1 showed a mean of 0.607 ± 0.007 mg/kg, RG2 at 0.458 ± 0.008 mg/kg, and RG3 at 0.7145 ± 0.001 mg/kg. The study found that rice cooked with tubewell water contained a higher arsenic concentration than rice cooked with rainwater. The most prominent finding of this study was that cooked rice using rainwater had a lower amount of arsenic than the raw rice grain. So, it is clearly said that using rainwater can minimize the amount of arsenic. Furthermore, the study indicates that the health risks associated with arsenic exposure have increased. Estimated daily intake (EDI) values for cooked rice samples ranged from 3.07 to 5.47 μg/kg body weight/day, exceeding safe limits. Target Hazard Quotient (THQ) values varied from 10.2 to 18.2, indicating significant potential for non-carcinogenic health effects. Lifetime Cancer Risk (LCR) values ranged from 0.461% to 0.821% exceeding the U.S. Environmental Protection Agency’s acceptable risk threshold of 0.01%, which reflects a heightened cancer risk. The study suggests that people in the study area should use rainwater instead of tubewell water for their cooking purposes. Furthermore, rainwater harvesting should be prioritized in this area to address arsenic issues.展开更多
Time series of daily UV radiation measured by the ground-based Brewer spectrophotometer #115 in Hong Kong during 1995-2005 were studied through statistics analysis, with focus on the variability and long term changes ...Time series of daily UV radiation measured by the ground-based Brewer spectrophotometer #115 in Hong Kong during 1995-2005 were studied through statistics analysis, with focus on the variability and long term changes in relation to total ozone, clouds and AOD (Aerosol Optical Depth). The 11-year mean UV daily dose is 2644±262 J/m2, with maxima(3311 J/m2) in 2000 and minima (2415 J/m2) in 2002. The data were compared with that from TOMS (Total Ozone Mapping Spectrometer) Version 8 and show general agreement between the two. However, the Brewer UV measurement is about 10% lower compared to TOMS data. Apart from the common-known strong seasonal cycle, 26 month periodical was resolved by use of wavelet analysis, which was believed to be associated with quasi-biennial oscillation (QBO) of general circulation. In cloudy days, the annual mean UV daily dose decrease 3.5% to 44.5% compared to clear days. It was also found that surface UV irradiance has close relation to air pollution. Under clear sky condition, 1% AOD increase will lead to 0.2% UV decrease. While global UV radiation increase due to the worldwide observed ozone depletion, investigations indicate that this trend is not significant in Hong Kong during the last 11 years. The possible causes can be attributed to the compensative effect from two aspects. One is the increase of UV resulting from the reduction of clouds with rate of 0.56/10 yr. The other is the decrease of UV due to the enhancement of total ozone and AOD with a rate of 4.23 DU/10 yr and 0.33/10 yr, respectively.展开更多
A chip-based spectrophotometer integrated with optical fiber is successfully demonstrated.Grade concentration of lactate solution flowed through the chip to perform an online detection.The response time (100s)and Limi...A chip-based spectrophotometer integrated with optical fiber is successfully demonstrated.Grade concentration of lactate solution flowed through the chip to perform an online detection.The response time (100s)and Limit of Detection (LOD, 50mg/L)of the device were measured.This device shows comparable performance with traditional commercial instrument, while greatly decreases the sample requirement per detection and reduces the size of total system,introducing a novel method for real-time detection.展开更多
The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and...The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and sodium cellulose glycolate as dispersing agent.The results showed that palladiumd thioglucoside method could be taken as a quick,easy and precise quantitative analysis method to determine thioglucoside in cabbage.展开更多
Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.Nat...Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.National Institute for Standards(NIS)in Egypt builds up aphotometric method to ensure the competence of absorbance and transmittance to the standard international and national requirements.This paper presents an instrument for UV-Vis measurement,discusses the factors affecting measurement reliability and estabishes the uncertainty model including correspoding measurement parameters.展开更多
Determination palladiums have been reported 5% (w/w) Pd/BaSO4 known as Rosenmund Catalyst. The determination of palladium II known as Rosenmund Catalyst is always an expensive procedure usually involving procedures su...Determination palladiums have been reported 5% (w/w) Pd/BaSO4 known as Rosenmund Catalyst. The determination of palladium II known as Rosenmund Catalyst is always an expensive procedure usually involving procedures such as flame atomic absorption spectrophotometry, emission spectrometry, and many spectrophotometric methods. In this study, palladium II in 5% Pd/BaSO4, was synthesized and employed to develop an extractive UV-Visible Spectrophotometric, and an inductively coupled plasma mass spectrometry ICP/MS methods for the determination of palladium II. Specification for Pd is 4.85% to 5.10%;the result was 4.97% for the UV-Visible spectrophotometer and 4.90% for the ICP/MS. Both results meet the requirements.展开更多
Background: The sunglass standards are not strictly implemented in many countries except Aus-tralia. The purpose of the study was to evaluate the optical properties of unbranded sunglasses for light transmittance. Met...Background: The sunglass standards are not strictly implemented in many countries except Aus-tralia. The purpose of the study was to evaluate the optical properties of unbranded sunglasses for light transmittance. Methods: Unbranded sunglasses with no information about their specifications were included. They were allocated to two groups based on their prices;the ones > 25 US$ (Group A) and the cheaper ones (Group B). Their transmittance spectrum was measured between 190 nm and 900 nm using a double beam scanning spectrophotometer. The European standard for sunglasses was used to evaluate their compliance regarding ultraviolet radiation (UVR) transmittance and minimum requirement for wearing when driving. Results: Thirty-eight sunglasses (Group A = 20 and Group B = 18) were evaluated. Four sunglasses in each group were non-compliant. Percentage transmittance of visible light was <8% in five sunglasses of Group A and in three of Group B, so these were not appropriate to wear when driving. Totally six sunglasses of Group A and five of Group B were non-compliant and/or inappropriate to wear when driving. Conclusions: Based on our findings about their UVR protection and visible light transmittance %, eye care professionals must warn people against the use of unbranded sunglasses without any information about their specifications.展开更多
<strong>Purpose:</strong> To investigate whether photodynamic diagnosis (PDD) using a portable fluorescence spectrophotometer (FC-1) can easily and objectively discriminate between normal and tumor cells a...<strong>Purpose:</strong> To investigate whether photodynamic diagnosis (PDD) using a portable fluorescence spectrophotometer (FC-1) can easily and objectively discriminate between normal and tumor cells at the dental chairside, and to further compare it with PDD that requires speculum examination by focusing on protoporphyrin IX (PPIX). <strong>Methods: </strong>Three cell lines (2 human oral squamous cell carcinoma-derived cell lines, HSC-2 and HSC-3 cells, and oral keratinocytes, HOK cells) were cultured. 5-Aminolevulinic acid hydrochloride (5-ALA) and deferoxamine mesylate (DFO) were mixed in DMEM, and the mixture was set to Control (DMEM only) and PDD (5-ALA+DFO) groups. And then, a fluorescence was measured under room temperature (RT) and 37°C (Incubation) by using FC-1. In this study, the two conditions were combined with the Control and PDD groups to form the Control/RT, Control/Incubate, PDD/RT, and PDD/Incubate groups. Additionally, the amount of singlet oxygen (1O2) generated by irradiation with 405 nm LED was measured using electron spin resonance spectroscopy to detect PPIX in the cell supernatant after 24 hours. <strong>Results:</strong> In HSC-2 and HSC-3, the fluorescence intensity values increased significantly at 2 hours between the Control/RT and PDD/RT groups. In addition, there was a significant difference between HSC-2 and HSC-3 compared to HOK. In all cell lines, the fluorescence intensity values of the PDD/Incubate group were significantly higher than those of the PDD/Control group. The amount of <sup>1</sup>O<sub>2</sub> generated by 405 nm LED irradiation was higher in the cell supernatants of all cell lines in the order of Control/RT < Control/Incubate < PDD/RT < PDD/Incubate group, and HSC-3 in the PDD/Incubate group showed a significant increase compared to HOK. <strong>Conclusion: </strong>It is suggested that PDD using FC-1 can clearly distinguish between normal cells and tumor cells in vitro studies using cell lines at 2 hours under 37°C, and it can detect not only intracellular PPIX, but also extracellular PPIX.展开更多
In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be...In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be lower than 25 × 10−3 g (http://file.scirp.org/pdf/JMP_2015082810060783.pdf). In this second paper, we attended measurement of GIAC-spectra. Unexpectedly, during the upwards movement, i.e. the hypergravity phase up to top acceleration values reaching 11.6 g at 35.4 s after liftoff we observed transient GIAC-spectra ranging from 380 to 750 nm. In addition, during the whole acceleration phase of 68.2 s, another component near 700 nm develops which remains stable during the whole “free fall trajectory parabola” for 381.3 s. The subsequent reentry of the rocket leads to extraordinary deceleration values up 37.8 g, completely destroying Phycomyces sporangiophores excluding their spectral measurement. During the microgravity phase and by centrifuge operation we were unable to detect any GIAC-spectra (in contrast to kinetic MDWS-measurements, first paper).展开更多
The measurement of lignin content in black liquid of straw AS-AQ by ultraviolet spectrophotometer(UV) is discussed in this paper. Different dilution multiple and contrast solutions have an effect on the measured resul...The measurement of lignin content in black liquid of straw AS-AQ by ultraviolet spectrophotometer(UV) is discussed in this paper. Different dilution multiple and contrast solutions have an effect on the measured results of the lignin content by UV. The calculation method for the absorption coefficient and the scanning spectrum property of liquor acidified by SO2 are introduced in this paper.展开更多
The advantage of electronic devices is to eliminate the subjectivity. Based on individual capabilities, visual perception has its disadvantages. The aim of this study was to find out the possible shade difference betw...The advantage of electronic devices is to eliminate the subjectivity. Based on individual capabilities, visual perception has its disadvantages. The aim of this study was to find out the possible shade difference between the upper and lower teeth, visual perception versus spectrophotometry as well as proving that females are better in visual perception of colour matching. 82 subjects (dental students) of this study determined the color of each other’s natural teeth. The color of 1640 teeth (incisors, canines and premolars), was matched by visual perception and by Vita Easyshade spectrophotometer. The matching was focused on the middle third of buccal surfaces of the examined teeth. In this study, it was found that there was a difference of color between the teeth of the upper and lower jaw. The percentage of the accordance between two methods was 28.35% for all examined teeth. The color determination at central incisors showed the highest value of accordance 40.85%. Based on Vitapan 3D Mastershade, the most frequent color was 2M2.展开更多
文摘Arsenic is a toxic element. Chronic exposure to arsenic can pose a variety of health problems including cancers, lung disease, skin lesions, diabetes, gangrene, reproductive disorders, hypertension, and heart disease. Globally the concern of arsenic is growing day by day. Addressing this concern, the study aimed to assess the arsenic level in raw rice grain and rice cooked with tubewell water and rainwater. The study was conducted at the Sholotaka Union of Gangni Upazila in Meherpur District of Khulna Division, Bangladesh in 2023. For this purpose, seven raw samples including rice grain, rainwater and tubewell water samples and six cooked rice samples were analyzed. Rice and water samples were digested using the USEPA method-3050B in Arsenic Center Jashore, under Asia Arsenic Network, Japan. The arsenic level in the samples was tested using the HG-AAS method using a Shimadzu model AA7000 (Japan) Atomic Absorption Spectrophotometer. The study’s findings revealed that arsenic concentration in rainwater samples consistently displays 0 mg/l indicating the absence of arsenic in this sample. Three (03) tube well water samples and three (03) raw rice grain samples showed a significant variation in arsenic concentration. The mean value of tubewell water samples T1, T2, and T3 was found 0.53 ± 0.003 mg/l, 0.31 ± 0.003 mg/l, and 0.65 ± 0.002 mg/l, respectively. Whereas raw rice grain samples RG1 showed a mean of 0.607 ± 0.007 mg/kg, RG2 at 0.458 ± 0.008 mg/kg, and RG3 at 0.7145 ± 0.001 mg/kg. The study found that rice cooked with tubewell water contained a higher arsenic concentration than rice cooked with rainwater. The most prominent finding of this study was that cooked rice using rainwater had a lower amount of arsenic than the raw rice grain. So, it is clearly said that using rainwater can minimize the amount of arsenic. Furthermore, the study indicates that the health risks associated with arsenic exposure have increased. Estimated daily intake (EDI) values for cooked rice samples ranged from 3.07 to 5.47 μg/kg body weight/day, exceeding safe limits. Target Hazard Quotient (THQ) values varied from 10.2 to 18.2, indicating significant potential for non-carcinogenic health effects. Lifetime Cancer Risk (LCR) values ranged from 0.461% to 0.821% exceeding the U.S. Environmental Protection Agency’s acceptable risk threshold of 0.01%, which reflects a heightened cancer risk. The study suggests that people in the study area should use rainwater instead of tubewell water for their cooking purposes. Furthermore, rainwater harvesting should be prioritized in this area to address arsenic issues.
文摘Time series of daily UV radiation measured by the ground-based Brewer spectrophotometer #115 in Hong Kong during 1995-2005 were studied through statistics analysis, with focus on the variability and long term changes in relation to total ozone, clouds and AOD (Aerosol Optical Depth). The 11-year mean UV daily dose is 2644±262 J/m2, with maxima(3311 J/m2) in 2000 and minima (2415 J/m2) in 2002. The data were compared with that from TOMS (Total Ozone Mapping Spectrometer) Version 8 and show general agreement between the two. However, the Brewer UV measurement is about 10% lower compared to TOMS data. Apart from the common-known strong seasonal cycle, 26 month periodical was resolved by use of wavelet analysis, which was believed to be associated with quasi-biennial oscillation (QBO) of general circulation. In cloudy days, the annual mean UV daily dose decrease 3.5% to 44.5% compared to clear days. It was also found that surface UV irradiance has close relation to air pollution. Under clear sky condition, 1% AOD increase will lead to 0.2% UV decrease. While global UV radiation increase due to the worldwide observed ozone depletion, investigations indicate that this trend is not significant in Hong Kong during the last 11 years. The possible causes can be attributed to the compensative effect from two aspects. One is the increase of UV resulting from the reduction of clouds with rate of 0.56/10 yr. The other is the decrease of UV due to the enhancement of total ozone and AOD with a rate of 4.23 DU/10 yr and 0.33/10 yr, respectively.
文摘A chip-based spectrophotometer integrated with optical fiber is successfully demonstrated.Grade concentration of lactate solution flowed through the chip to perform an online detection.The response time (100s)and Limit of Detection (LOD, 50mg/L)of the device were measured.This device shows comparable performance with traditional commercial instrument, while greatly decreases the sample requirement per detection and reduces the size of total system,introducing a novel method for real-time detection.
文摘The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and sodium cellulose glycolate as dispersing agent.The results showed that palladiumd thioglucoside method could be taken as a quick,easy and precise quantitative analysis method to determine thioglucoside in cabbage.
文摘Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.National Institute for Standards(NIS)in Egypt builds up aphotometric method to ensure the competence of absorbance and transmittance to the standard international and national requirements.This paper presents an instrument for UV-Vis measurement,discusses the factors affecting measurement reliability and estabishes the uncertainty model including correspoding measurement parameters.
文摘Determination palladiums have been reported 5% (w/w) Pd/BaSO4 known as Rosenmund Catalyst. The determination of palladium II known as Rosenmund Catalyst is always an expensive procedure usually involving procedures such as flame atomic absorption spectrophotometry, emission spectrometry, and many spectrophotometric methods. In this study, palladium II in 5% Pd/BaSO4, was synthesized and employed to develop an extractive UV-Visible Spectrophotometric, and an inductively coupled plasma mass spectrometry ICP/MS methods for the determination of palladium II. Specification for Pd is 4.85% to 5.10%;the result was 4.97% for the UV-Visible spectrophotometer and 4.90% for the ICP/MS. Both results meet the requirements.
文摘Background: The sunglass standards are not strictly implemented in many countries except Aus-tralia. The purpose of the study was to evaluate the optical properties of unbranded sunglasses for light transmittance. Methods: Unbranded sunglasses with no information about their specifications were included. They were allocated to two groups based on their prices;the ones > 25 US$ (Group A) and the cheaper ones (Group B). Their transmittance spectrum was measured between 190 nm and 900 nm using a double beam scanning spectrophotometer. The European standard for sunglasses was used to evaluate their compliance regarding ultraviolet radiation (UVR) transmittance and minimum requirement for wearing when driving. Results: Thirty-eight sunglasses (Group A = 20 and Group B = 18) were evaluated. Four sunglasses in each group were non-compliant. Percentage transmittance of visible light was <8% in five sunglasses of Group A and in three of Group B, so these were not appropriate to wear when driving. Totally six sunglasses of Group A and five of Group B were non-compliant and/or inappropriate to wear when driving. Conclusions: Based on our findings about their UVR protection and visible light transmittance %, eye care professionals must warn people against the use of unbranded sunglasses without any information about their specifications.
文摘<strong>Purpose:</strong> To investigate whether photodynamic diagnosis (PDD) using a portable fluorescence spectrophotometer (FC-1) can easily and objectively discriminate between normal and tumor cells at the dental chairside, and to further compare it with PDD that requires speculum examination by focusing on protoporphyrin IX (PPIX). <strong>Methods: </strong>Three cell lines (2 human oral squamous cell carcinoma-derived cell lines, HSC-2 and HSC-3 cells, and oral keratinocytes, HOK cells) were cultured. 5-Aminolevulinic acid hydrochloride (5-ALA) and deferoxamine mesylate (DFO) were mixed in DMEM, and the mixture was set to Control (DMEM only) and PDD (5-ALA+DFO) groups. And then, a fluorescence was measured under room temperature (RT) and 37°C (Incubation) by using FC-1. In this study, the two conditions were combined with the Control and PDD groups to form the Control/RT, Control/Incubate, PDD/RT, and PDD/Incubate groups. Additionally, the amount of singlet oxygen (1O2) generated by irradiation with 405 nm LED was measured using electron spin resonance spectroscopy to detect PPIX in the cell supernatant after 24 hours. <strong>Results:</strong> In HSC-2 and HSC-3, the fluorescence intensity values increased significantly at 2 hours between the Control/RT and PDD/RT groups. In addition, there was a significant difference between HSC-2 and HSC-3 compared to HOK. In all cell lines, the fluorescence intensity values of the PDD/Incubate group were significantly higher than those of the PDD/Control group. The amount of <sup>1</sup>O<sub>2</sub> generated by 405 nm LED irradiation was higher in the cell supernatants of all cell lines in the order of Control/RT < Control/Incubate < PDD/RT < PDD/Incubate group, and HSC-3 in the PDD/Incubate group showed a significant increase compared to HOK. <strong>Conclusion: </strong>It is suggested that PDD using FC-1 can clearly distinguish between normal cells and tumor cells in vitro studies using cell lines at 2 hours under 37°C, and it can detect not only intracellular PPIX, but also extracellular PPIX.
文摘In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be lower than 25 × 10−3 g (http://file.scirp.org/pdf/JMP_2015082810060783.pdf). In this second paper, we attended measurement of GIAC-spectra. Unexpectedly, during the upwards movement, i.e. the hypergravity phase up to top acceleration values reaching 11.6 g at 35.4 s after liftoff we observed transient GIAC-spectra ranging from 380 to 750 nm. In addition, during the whole acceleration phase of 68.2 s, another component near 700 nm develops which remains stable during the whole “free fall trajectory parabola” for 381.3 s. The subsequent reentry of the rocket leads to extraordinary deceleration values up 37.8 g, completely destroying Phycomyces sporangiophores excluding their spectral measurement. During the microgravity phase and by centrifuge operation we were unable to detect any GIAC-spectra (in contrast to kinetic MDWS-measurements, first paper).
文摘The measurement of lignin content in black liquid of straw AS-AQ by ultraviolet spectrophotometer(UV) is discussed in this paper. Different dilution multiple and contrast solutions have an effect on the measured results of the lignin content by UV. The calculation method for the absorption coefficient and the scanning spectrum property of liquor acidified by SO2 are introduced in this paper.
文摘The advantage of electronic devices is to eliminate the subjectivity. Based on individual capabilities, visual perception has its disadvantages. The aim of this study was to find out the possible shade difference between the upper and lower teeth, visual perception versus spectrophotometry as well as proving that females are better in visual perception of colour matching. 82 subjects (dental students) of this study determined the color of each other’s natural teeth. The color of 1640 teeth (incisors, canines and premolars), was matched by visual perception and by Vita Easyshade spectrophotometer. The matching was focused on the middle third of buccal surfaces of the examined teeth. In this study, it was found that there was a difference of color between the teeth of the upper and lower jaw. The percentage of the accordance between two methods was 28.35% for all examined teeth. The color determination at central incisors showed the highest value of accordance 40.85%. Based on Vitapan 3D Mastershade, the most frequent color was 2M2.