Flame Photometry Method Research Articles

Aluminum waste in alumina cement production (Mikhailovka)

Alumina cement is a rapidly hardening hydraulic binder containing low-basic calcium aluminates in the final product. The alumina cement production by melting is widespread. Melting of the mixture consisting of bauxite and limestone is carried out in the temperature range of 1500 to 1600 °C, which entails enormous energy consumption and, accordingly, the higher cost of resulting products. The paper studies the possibility of reducing the melting point as well as the cost of the main mixture component bauxite via its replacement by aluminum-containing waste.Purpose: Suggest the dependence between the mixture composition and the Al2O3 content in the initial aluminum waste; determine the best annealing temperature for alumina clinker; study strength properties of the resulting alumina cement and the effect of introduced limestone on the main quality index.Methodology: The chemical composition of the aluminum waste (sludge and powder), raw mixtures, and resulting clinker are detected in laboratory conditions using spectrophotometry and flame photometry methods in accordance with the state standard. X-ray phase analysis of waste and clinker is based on the powder diffraction method and conducted on the Thermo Scientific ARL X'TRA Powder Diffractometer. Physical and mechanical tests are carried out in accordance with the state standard poly-fraction sand.Research findings: Laboratory studies show that aluminum waste (sludge and powder), consisting of gibbsite and boehmite in combination with limestone, is suitable for the production of alumina clinker. Depending on the initial Al2O3 content, their content in the raw mixture ranges from 60 to 75 %.Value: Depending on the composition, the fest annealing temperature for alumina clinker, is 1350 to 1400 ℃; the mineralogical composition of clinkers consists of 85–90 % calcium aluminates. Alumina cement strength determined in small test samples having normal density and the ratio 1:0, is high after 2 days and ranges from 33.7 to 40.6 MPa. The addition of 5 % crystalline limestone into cement accelerates the initial rate of hardening and improves the strength from 33.7 to 53.2 MPa after 2 days due to the additional formation of 3CaO·Al2O3·CaCO3·11H2O.

Determination of Potassium in Empty Bunches Palm Oil (Elaeis guineensis Jacq.) Using Flame Photometry Method

Research on the determination of potassium in empty bunches palm oil have been done with the flame photometry method. The samples were taken randomly from five areas in Northen Sumatera with various heights in the range of < 25- 400 m above sea level. The first sampling was of Datuk Bandar district at Tanjung Balai < 25 m, Meranti district at Kisaran 50 to 100 m, Bosar Maligas district at Simalungun 150-200 m, Simarimbun district at Pematang Siantar 250 to 300 m, and the last Sari Matondang district at Sidamanik 350-400 m. The sample was digested using concentrated nitric aid and 30% hydrogen peroxide then heated with the addition of nitric acid concentrated. Potassium content was measured with a flame photometer at specific 767.5 nm by using calibration methods. The result obtained that potassium contents in the samples were 11.83%; 17.56%; 21.89%; 24.68%, and 25.14% for Tanjung Balai, Kisaran, Simalungun, Pematang Siantar, and Sidamanik respectively. The data obtained showed the higher area of the sea, the lower the temperature so the content of potassium increased in the palm oil empty bunches.

Assessment of the Hydrogeochemistry of the Groundwater Resources of Gwoza, Northeastern Nigeria

The study was carried out in Gwoza town of Borno Sate to assess the chemistry of groundwater of Gwoza Local Government. Eighteen (18) groundwater samples were collected for the purpose of this study; samples were analyzed for their physical parameters at spot using field kits combined pH/EC/TDS/Temperature meter model Mi 806 were also used for measuring physical parameters. GPS was used in locating the sampling points. Sodium and Potassium were analyzed by flame photometry method; Calcium and Magnesium were determined by Atomic Absorption Spectrometry method using AAS-400 PerkinElmer model type. Iron was determined using spectrophotometer, Photometric method was used to determine sulphate while chloride was analysed using argentometric of bicarbonate HCO3- and carbonate CO3-2 From the result obtained Na+ range from 26-200 mg/L, K range from 7 – 59 mg/L, Ca+2 range from 45- 290 mg/L, Cl-2 range from 20 – 264 mg/L, HCO3-2 range from 120.06 - 292 .9 mg/L, NO3-2 range from 14 – 670 mg/L, SO4 range from 0 – 79 mg/L, Fe2+ range from 0.08 – 0.44 mg/L, Mn+2 range from 0.00 – 0.20 mg/L and Mg2+ range from 0.45 – 1.95 mg/L. The results of the analyses were compared with the WHO standards of drinking water indicates that Cl-2 and NO3-2 in some locations are above the permissible limit while all other elements are within the set standard. Therefore the water is not safe for drinking and bacteriological analysis is recommended for the area.

IMPACT OF SALT REDUCTION ON BREAD ON SENSORY PREFERENCE AND PHYSICOCHEMICAL PARAMETERS

Purpose The purpose of this study was to evaluate the impact of salt reduction on bread physicochemical parameters and sensory analysis. The relationship between sensory attributes and preference was assessed using external preference mapping (PREFMAP). Moreover, sensory attributes relationship with physicochemical parameters was evaluated. Methodology Four Portuguese bread formulations were tested: “D’água”, “Carcaça”, “Mistura”, and “Regueifa”, produced with different salt concentrations (0.0%, 0.8%, 1.0%, 1.1%, 1.3%, and 1.4% of salt per wheat flour). Bread physicochemical characteristics evaluated included weight, volume, moisture, salt content, and crumb colour and structure. Sodium was determined by flame photometry method, while crumb colour and structure by digital image analysis. Sensory analysis was carried out with 8 trained assessors and consumer test with 80 participants. Statistical models for sensory preference evaluation were developed using PREFMAP. Statistical comparison was performed using as control bread with 1.4% of salt (legal value allowed). Findings Overall, salt reduction had significant impact on moisture, salt content and colour parameters, but limited influence on crumb morphology. Salt reduction had a significant negative impact on overall assessment, taste liking and overall linking attributes. The lowest salt concentrations with best consumer acceptance were: 0.8% (“D’Água” and “Carcaça”), 1.0% (“Mistura”), and 1.1% (“Regueifa”). These results suggest that salt reduction in these breads is possible without major impact on bread characteristics and without compromising consumers’ acceptance.

Radiographic and Biochemical Evaluations of Postnatal Development of Bones of the Forelimb in Nigerian Indigenous Dogs.

Bone is a hard and resilient tissue structure that provides mechanical support for the body of an organism. This study was aimed to evaluate the radiographical and biochemical changes during postnatal bone development of forelimbs in Nigerian indigenous puppies from 2-week-old to 24-week-old. Six (6) Nigerian indigenous puppies were chemically restrained using chlorpromazine at 2 mg/kg I.M. and positioned using ropes and sandbags for mediolateral and craniocaudal views of bones of the forelimbs. At 2-week-old, radiographic evaluation of bones of the forelimbs were undertaken and continued bi-weekly up to 24-week-old. Serum samples were analysed from 4-week-old to 24-week-old at four weeks’ interval for mineral (electrolytes) using colometric method for calcium and phosphorus and flame photometry method for sodium and potassium. At 2-week-old, there was an ill-defined radiopaque secondary ossification centre at the proximal epiphysis and a small ovoid radiopaque structure at the distal epiphysis of the humerus. There was not any sign of secondary ossification centre at proximal and distal epiphyses of both radius and ulna. There was the presence of a small radiopaque (ill-defined) accessory carpal. 1st to 5th metacarpals were present together with the proximal, middle and distal phalanges of all digits except the 1st digit that has proximal and distal phalanges. From 20-week-old, fully developed carpals and bony structures were observed through 24-week-old where the commencement of fusion of apophyses of olecranon (proximal epiphysis of ulna) at the centre and acrophyses of metacarpals and phalanges. The mean values (mean ± SEM) from serum biochemistry of calcium, phosphate, sodium and potassium in mmol/L from this study were within the normal limits throughout the study. Conclusively, the complementary information from calcium, phosphate, sodium and potassium in this study showed that these elements are within the normal limit that suggests normal bone development during the study period, which stressed the importance of the knowledge on serial changes of bone development which could be useful in clinical practice.

Assessment of Hydrochemistry, Facies Type and Processes Contributing the Major Ions to the Groundwater of Ajakanga Area, Ibadan, South Western Nigeria

Resulting from insufficient supply of potable water and risk of possible contamination from anthropogenic sources, 14 samples were collected from wells at Ajakanga and environs in Ibadan, Southwestern Nigeria, in order to determine the shallow groundwater quality and desirability for drinking purposes. Physical parameters such as pH, EC, and TDS were measured at site using a combined EC, TDS and pH meter. Major ions analyzed included Na+, Ca2+, Mg2+, K+, NO3-, Cl-, HCO3- and SO42-. The anions were measured using titrimetric method, and analyzed by Genesys 2.0 Spectrophotometer, while the cations were analyzed using the flame photometry method. The hydrochemical data were subjected to a series of statistical analysis and conventional graphical plots. Results showed that all the chemical parameters analyzed, excepting Cl- fall within the World Health Organization permissible limit for drinking water. The shallow groundwater is therefore fit for drinking purposes. Cations concentration in the water is in the order of Ca>Mg>Na>K, while for the major anion HCO3>Cl>SO4>NO3. Scatter plots and Gibbs diagram showed that the cations were released into the water as a result of weathering of the underlying basement rocks. Trilinear Piper diagram indicated two water facies in the area, with CaHCO3 water being dominant, while CaMgHCO3 is subordinate. Application of Chloro Alkaline Indices and the Ca/HCO3 ratio indicated that reverse ion exchange reaction is responsible for the dominance of Ca2+ and Mg2+ in the waters.

Abstract P226: Changes of Blood Pressure and Urinary Sodium Over 18 Years in Rural China: Results From the INTERMAP China Prospective Study

Background: Tremendous dietary pattern changes could be a driver of the increasing burden of high blood pressure (BP) in developing countries. However, data on nutrition transitions and associated BP changes are scarce. Objective: To explore BP changes and sodium (Na) consumption over 18 years in China. Methods: International Collaborative Study of Macro-/Micro-nutrients and Blood Pressure (INTERMAP) enrolled 839 men and women aged 40-59 years from three geographically diverse regions (Beijing, Shanxi in the north and Guangxi in the south) in 1997. INTERMAP China Prospective (ICP) Study followed up these three populations in 2015-2016. Seated BP were measured at least twice following at least 5 minutes of rest, using a random zero sphygmomanometer for the INTERMAP (baseline) and an oscillometric device (Omron HEM-907) for the ICP (follow-up). When calculating BP changes, baseline values were converted using equations developed in a calibration study. Timed 24-hr urine samples were collected at baseline and follow-up using the same protocol. Urinary Na and creatinine (Cr) were measured by emission flame photometry method at baseline and ion-selective electrode method at follow-up. BP and dietary Na changes over time were compared using student t test. Results: Systolic BP increased considerably in all three sites; largest increment in Guangxi (18.6, 95% CI: 16.0-21.1 mm Hg, P<0.001) and smallest in Beijing (9.1, 6.3-11.8 mm Hg, P<0.001) (Table 1). Level of urinary Na was almost double in north (Beijing and Shanxi) than south (Guangxi) at follow-up (P<0.001), similar as baseline. On average, participants consumed 10.8 (4.7) and 11.8 (4.7) grams of salt at Beijing and Shanxi and 6.3 (3.0) grams of salt at Guangxi at follow-up, though a trend of reduction in Na/Cr (-3.7, 95% CI: -4.7- -2.6, P<0.001) overall was documented. Conclusions: Systolic BP levels increased considerably in this cohort between 1997 and 2015 in rural China. Na consumption might have a declining trend, but still at a very high level at northern China.

The relationship between serum zinc levels and rheumatoid arthritis activity

Rheumatoid arthritis (RA) is one of the most prevalent chronic autoimmune diseases; it typically involves the hands, wrists, ankles, and eventually all joints. Some studies have reported that zinc serum levels are lower in patients with RA than in healthy individuals. Seventy-nine patients with RAwere selected. The patients were all less than 75 years old and were diagnosed by a rheumatologist. Serum zinc levels were measured using the flame photometry method with a blood sample of 5 mL. The relationship between the average serum zinc level and disease activity was analyzed based on the DAS28 scoring scale for different RA groups. The significance threshold was set at p<0.05. Data analyses were implemented in SPSS 22.0. There was a significant inverse relationship between the serum zinc levels and disease activity. Chi-square tests were used to compare zinc serum levels with respect to disease activity. There were significant differences in zinc levels among three groups of patients with different levels of disease severity, such that disease activity increased as the serum zinc level decreased (p<0.001). There was a significant inverse relationship between the serum zinc level and RA activity based on the DAS28 score. Therefore, it is recommended that mineral deficiencies should be addressed by optimizing the zinc supply along with other standard medications in order to reduce RA activity.

Validation of a flame photometric method for serum lithium estimation

Background Lithium is a first line drug used to treat bipolar affective disorder requiring frequent monitoring due to its narrow therapeutic index. Flame photometry is a reliable quick and cost-effective method of serum lithium estimation. Objective We aimed to validate a flame photometry method for serum lithium estimation to compare the results with a different model flame photometer and an ion-selective electrode. Method Sherwood 410 flame photometer was used for the analysis. Serum samples were diluted 1:2 using a lithium blank solution containing sodium and potassium. Aqueous lithium standards were prepared using the same blank. The method was validated for the concentration range 0.2-1.5mmol/l. Linearity, recovery, accuracy, precision and stability were determined by standard lithium serum samples representing the lower limit of quantification (LLOQ) 0.2mmol/l, median level of quantification (MLOQ) 0.8mmol/l and the upper limit of quantification (ULOQ) 1.5mmol/l. Five replicates of serum and aqueous lithium samples were used to determine linearity in the range between LLOQ and ULOQ using the coefficient of determination (R2). Five standard serum replicates were used for recovery, accuracy and precision studies. Precision was determined by the coefficient of variation (CV%) on three different days. Results of the flame photometric method were compared with those of a different flame photometric method and an ion-selective electrode method. Results: The R2 for the aqueous samples and the serum samples was >0.995 demonstrating linearity. The matrix effect ranged between 92.5% and 105% for the LLOQ, MLOQ and ULOQ. The accuracy and precision for LLOQ, MLOQ of and ULOQ were below 15%. Similar results were obtained for the QC samples with the different model flame photometer and ion-selective electrode method. Conclusion The flame photometric method used in our laboratory is suitable and reliable for determining serum lithium concentrations for use in therapeutic drug monitoring.

Examination of the effectiveness of filtering half masks protection at various flow rates of aerosol contaminants

The possibility of air contamination by biological agents, by natural or artificial way, requires the improvement and use of different means for respiratory protection. The paper presents comparative filtration efficiency testing of different filtering half masks models, in order to determine the possibility of using this means for respiratory protection of the Ministry of Defence and the Serbian Army members. As a test agent and an appropriate simulator of biological aerosols is used solid NaCl aerosol. Determination of the concentration of the test aerosol at various flow rates was performed by flame photometry method. It was found that all the tested models are manufactured from filtering material of high quality and that filtering materials of lower quality shows less differences between filtering characteristics at lower flow rates. The high efficiency of the tested filtering half masks models provides an opportunity for their use in respiratory protection.

A Study of Salt Content of Different Bread Types Marketed in Amman, Jordan

&lt;p&gt;Noncommunicable diseases, including cardiovascular diseases are the leading cause of premature death in the 21st century. Dietary factors such as high salt intake constitute the main risk factors. Bread is considered as one of the most important sources of dietary salt. The objectives of this study were to determine the sodium content of the main types of bread that are marketed in Amman, and to evaluate the bakers’ adherence to the Jordanian specifications. Sixty eight bread samples of seven types of bread were collected from 13 different bakeries distributed in Amman. Bread samples were dried, ashed and the sodium content was directly determined by using flame photometry method. The average salt content of the analyzed bread samples was 1.19±0.21 g salt/100 g of fresh bread, ranging between 0.42 g/100 g for white Arabic bread and 2.06±0.19 for &lt;em&gt;shrak&lt;/em&gt; bread. Approximately half of bread samples have met the Jordanian specifications. It is concluded that salt content of bread varies widely in Jordan and that bread types such as &lt;em&gt;shrak&lt;/em&gt; and &lt;em&gt;mashrouh&lt;/em&gt; breads contain high amount of salt. The Jordanian specification of the salt content of bread should be applied to all breed types. Also, it should be reduced gradually to a lower limit.&lt;/p&gt;

Evaluation of Two Indigenous Multipurpose Shrub Species for Agroforestry Practices in Nigeria

Trees integrated with crops in time and space help nutrient cycling on farms by increasing the supply and availability of nutrient in the crop root zone and reducing nutrient losses. An analysis to determine the nutrient composition of two indigenous multipurpose shrubs (Uvaria chamae p. beauv and Icacina trichantha oliv) of Akwa Ibom State, Nigeria, was conducted in the lowland rainforest agro-ecological zone. The roots and leaves of the shrubs were collected from the three agro-ecological (mangrove, freshwater swamp and lowland rainforest) zones and analysed for nutrient contents including the soils. Nitrogen content was determined using Kjeldahl method while phosphorus and potassium were determined by flame photometry method. The results indicated a great variability in the nutrient composition of the two species. Nitrogen content in the leaves and roots of Icacina trichantha was 2.78% and 1.17% while that of Uvaria chamae was 1.85% and 0.65% respectively. The percentage phosphorus composition in the roots of Icacina trichantha was 0.09% while that of Uvaria chamae was 0.07%. Whereas in the leaves sample, Uvaria chamae had phosphorus content of 0.10%, the percentage composition of potassium in Uvaria chamae was 0.09% while Icacina trichantha had 0.05% respectively. In the roots, Icacina trichantha and Uvaria chamae had 0.11% and 0.09% potassium content respectively. The two indigenous multipurpose shrubs contained essential nutrient sources for growth and high crop yield. It is therefore recommended that farmers could intercrop these species with food crops in their farmland to improved soil fertility.Keywords: Evaluation, indigenous, multipurpose shrubs, agroforestry, Nigeria

Using chemometric methods for overlap correction of sodium-zinc spectral lines generated by wavelength dispersive X-ray fluorescence in mineral samples

Partial least squares, principal component regression and support vector machine multivariate methods were used for overlap correction of sodium–zinc (Na(Kα)–Zn(Lα)) spectral lines generated by means of wavelength dispersion X-ray fluorescence (WDXRF) combined with standard-less software (IQ+) technique for the analyses of mineral samples. This methodology uses one scan channel using PX1 analyzer crystal, 550-µm collimator, flow detector (Ar + CH4), and rhodium (Rh) tube for determination of Na and Zn in mineral compositions in minimum time. The calibration matrix was made up of 35 samples containing different amounts of Na2O and ZnO. The considered concentration ranges were 0–5% for both Na2O and ZnO. The values for 2θ angle were recorded between 25° and 29.9° at every 0.1°. Variable tube powers (kV − mA) were used to investigate the effect of tube power on the analyses of elements. The validation of the multivariate methods was realized by analyzing soil samples. Atomic absorption and flame photometry methods were used as reference methods for analyzing Zn and Na in the soil samples, respectively. The results of using chemometric methods, WDXRF (standard-less software) and reference method determined partial least squares and support vector machine models obtained more acceptable results for Na2O in presence of ZnO than those of WDXRF (standard-less software). Copyright © 2013 John Wiley & Sons, Ltd.

Testing the protective efficiency of personal respiratory protection devices in radiologically contaminated environments

The use of ammunition primed with depleted uranium is one of the hallmarks of modern combat operations, resulting in environmental contamination by particles of depleted uranium and uranium oxide, scattered around in the form of submicron-scale aerosols. This paper examined the protective effectiveness of the Serbian military's M3 protective face mask in relation to the presence of airborne depleted uranium and its by-products. Sodium chloride in solid aerosol form was used as a test substance and adequate physical simulator of such radioactive aerosols because its granulometric (particle) size distribution met the requirements of suitability as a simulator. Determination of aerosol concentration was carried out by flame photometry method, whilst granulometric distribution was determined by an electric particles analyzer. It was established that the total internal leakage of the M3 protective mask was as much a function of the penetration of particles through the combined M3 filter as of the leaks along the fitting line of the user's face mask and the inhalation valve. In terms of its protective effect against aerosols of depleted uranium and associated oxides, the Serbian M3 protective mask was determined to be of high efficiency and physiological suitability.

Agreement of Two Different Laboratory Methods Used to Measure Electrolytes

Aim:The aim of our study was to do an agreement analysis of two different laboratory methods used to measure electrolytes i.e., between the ISE based Beckman Coulter Synchron CX9 PRO Biochemistry analyzer and RAL's Ion3 Flame Photometer (Técnica para el Laboratorio, Barcelona, Spain), in serum samples.Materials and Methods:This cross sectional study was done over a period of three months from September’09 through December’09 on routine biochemistry samples. A total of 6492 samples were received for routine biochemistry analysis from those 630 blood samples were randomly processed for this study. Two ml of sample was taken in a plain gel tube (LABTECH Disposables, Ahmedabad, India), centrifuged and further processed using both systems within one hour of the sampling to obtain the Na and K concentrations in the samples. The bias and variability of differences in measured values were analyzed according to Bland and Altman method.Results:Flame photometry method has drawbacks such as low throughput, requires manual operation, is a time consuming procedure. Ion selective electrodes technique is a more universal method for the high throughput determination of electrolytes in physiological samples; Beckman Coulter Synchron CX9 PRO is an example of such a system. The mean difference between the two methods (standard minus test) and 95% limits of agreement for sodium in serum was -7.8±17.3 (-42.2 to 26.6) and in urine was -22±41 (-104 to 60). Similarly, the mean difference between the two methods for potassium values in serum was found to be -0.25±0.75 (-1.75 to 1.25) and in urine was -5.3±38.9 (-83.1 to 72.5). With 95% confidence interval, the value of sodium and potassium as determined by both the methods lie between the upper and lower limit showing 95% limits of agreement.Conclusion:Good degree of agreement was seen on comparing the two methods for measuring the electrolytes; the use of Synchron CX9 in place of Flame photometer for electrolyte analysis in serum and urine is justified or use the two interchangeably.

Pseudohyponatremia: Does It Matter in Current Clinical Practice?

Serum consists of water (93% of serum volume) and nonaqueous components, mainly lipids and proteins (7% of serum volume). Sodium is restricted to serum water. In states of hyperproteinemia or hyperlipidemia, there is an increased mass of the nonaqueous components of serum and a concomitant decrease in the proportion of serum composed of water. Thus, pseudohyponatremia results because the flame photometry method measures sodium concentration in whole plasma. A sodium-selective electrode gives the true, physiologically pertinent sodium concentration because it measures sodium activity in serum water. Whereas the serum sample is diluted in indirect potentiometry, the sample is not diluted in direct potentiometry. Because only direct reading gives an accurate concentration, we suspect that indirect potentiometry which many hospital laboratories are now using may mislead us to confusion in interpreting the serum sodium data. However, it seems that indirect potentiometry very rarely gives us discernibly low serum sodium levels in cases with hyperproteinemia and hyperlipidemia. As long as small margins of errors are kept in mind of clinicians when serum sodium is measured from the patients with hyperproteinemia or hyperlipidemia, the present methods for measuring sodium concentration in serum by indirect sodium-selective electrode potentiometry could be maintained in the clinical practice.

ORGANIC FARMING AS A SYSTEM TO PROVIDE BETTER VEGETABLE QUALITY

ORGANIC FARMING AS A SYSTEM TO PROVIDE BETTER VEGETABLE QUALITY

Twenty-four hour urinary sodium and 3-methylhistidine excretion in relation to blood pressure in Chinese: results from the China-Japan cooperative research for the WHO-CARDIAC Study.

We examined the associations between sodium and blood pressure (BP), and between 3-methylhistidine (3MH) (a marker of animal protein intake) and BP in four Chinese population samples (Guiyang, Guangzhou, Shanghai and Shijiazhuang). This work was a constituent part of the World Health Organization (WHO) Cardiovascular Disease and Alimentary Comparison (CARDIAC) Study. Each population sample consisted of 100 men and 100 women aged 48-56 yr and randomly selected using a cross-sectional study design. Twenty-four hour urine samples were collected. Urinary sodium and potassium excretion levels were measured by the flame photometry method, and 3MH was measured using a Hitachi Amino Acid Analyzer 835 (Hitachi, Ibaraki, Japan). After excluding subjects who did not complete the 24-h urine collection (as assessed by urinary creatinine excretion in relation to weight), the total study group included 314 men and 355 women. The results showed that (1) Sodium was positively, and 3MH negatively associated with systolic and diastolic BP (SBP, DBP) in both the total sample and in those who were not administered anti-hypertensive drugs; these associations were all significant (p< 0.05), and remained so after adjustment for age, sex, body mass index [BMI, weight (kg)/height (m2)], alcohol intake and potassium excretion. Sodium and 3MH were also observed to exert a combined effect on BPs. In general, subjects who had higher sodium and lower 3MH levels had higher mean SBP and DBP. This combined effect was particularly clear on SBP. (3) A positive association between sodium and BP, and a negative association between 3MH and BP were also shown in subjects who had BMI less than 26 kg/m2. In conclusion, the study confirmed and further extended previous observations on the study of salt and animal protein intake in relation to BP in middle-aged Chinese. The results support recommendations for a reduction in high salt intake for the control of high BP in the general population and in those with lower BMI. The results also provide important evidence that adequate animal protein intake may have a favorable effect on BP.

Study of the errors of the flame photometry method for drug analysis applications

Study of the errors of the flame photometry method for drug analysis applications

Comparison of an inductively coupled plasma-atomic emission spectrometry method for the determination of calcium, magnesium, sodium, potassium, copper and zinc with atomic absorption spectroscopy and flame photometry methods

Serum calcium, magnesium, copper and zinc concentrations obtained from the analysis of 77 serum samples by inductively coupled plasma-atomic emission spectrometry (ICP-AES) are compared with the results obtained using atomic absorption spectroscopy (AAS). Similarly, serum sodium and potassium levels from the analysis of the same samples by ICP-AES are compared with the levels obtained by flame photometry. For each metal, we compare the results from both methods with a linear regression program that assumes error in both variables. The regression analysis shows that the ICP-AES method gives slightly higher calcium, copper, and zinc results and lower magnesium results than the AAS methods, and lower sodium and potassium results than the flame photometry method. Except for sodium, the correlation ( r) between the results is very high (⩾0.958), indicating that the ICP-AES results could be corrected to be equivalent to the atomic absorption or flame photometry results. The ICP-AES has the advantage of requiring less preparation and analysis time, and additional elements could be determined simultaneously in the same sample.