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1
Rajkovic, Milos, Ivana Sredovic, and Zorana Miloradovic. "Comparison of different methods for determination of sodium chloride in cheese." Journal of Agricultural Sciences, Belgrade 55, no. 1 (2010): 65–77. http://dx.doi.org/10.2298/jas1001065r.
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The content of NaCl (weight fraction of Cl-ions, in %) was analysed in different cheeses, which were bought in supermarkets, and made by domestic manufacturers. Sodium chloride in cheese samples was analysed after the extraction of chloride by nitric acid solution. Concentration of chloride ions was potentiometricly determined, with the chloride selective electrode and titrimetricly by Volhard method. According to the results in the analysis of the content of NaCl in %, by different methods it was determined that the share of NaCl in % ranged from 0.66 to 4.43% (determined by potentiometric route) that is from 0.97 to 4.72% (determined by titrimetric route by Volhard method). The difference in received results in different methods is less if the share of NaCl, in % is higher than 3%. If the share is less than 3%, the difference in results rapidly increases, and the biggest difference is when the share is less than 1%. This analysis was done according to the results received by Volhard method, which is accepted as a standard method. As Volhard method is in connection with cheese resolving by intense oxidation means, azotic acid and potassium permanganate, obligatory in fume board (hood), it is not a practical method. On the other hand, the potentiometric method with usage of the chloride-selective electrode is very simple and gives reliable and reproductive results. In case of a small content of NaCl, in %, higher precision and accuracy of determination by chloride-selective electrode can be obtained by indirect measurement of chloride-ions (by standard addition method).
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Beljaars, Paul R., and William Horwitz. "Comparison of the Volhard and Potentiometric Methods for the Determination of Chloride in Meat Products: Collaborative Study." Journal of AOAC INTERNATIONAL 68, no. 3 (May 1, 1985): 480–84. http://dx.doi.org/10.1093/jaoac/68.3.480.
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Abstract A collaborative study of the determination of chloride in meat products was conducted by the International Organization for Standardization (ISO) to compare the ISO 1841 method (Volhard titration) with the FAO/WHO Codex Alimentarius Committee method (potentiometric titration). Five canned luncheon meat products containing 0.25-2.0% sodium chloride at 4 different spiking levels were analyzed by 11 laboratories. The data were analyzed by ISO statistics (ISO 5725) and by AOAC statistics (Youden-Steiner), the major differences being in the rejection of outliers and in the statement of precision parameters. Good agreement was found between the mean chloride contents of the products as determined by both methods and with the added amounts, although statistically significantly higher sodium chloride recoveries were obtained with the potentiometric method. The within-laboratory variability (repeatability) is greater for the Volhard method, especially for chloride levels below 1.0%. Therefore it is proposed to set the lowest level of determination for the Volhard method at about 1.0% sodium chloride. The among-laboratories variability (reproducibility) of the potentiometric method was comparable with the results from the collaborative studies for chloride in cheese, giving acceptable values for relative standard deviations of 1.5-3.0% for meat products with 0.3-2.0% added sodium chloride. It is recommended that further work be conducted to reduce or eliminate the systematic error present with the potentiometric method as applied to meat and meat
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Haouet, M. Naceur, M. Serena Altissimi, Marisa Framboas, and Roberta Galarini. "Validation of the Volhard method for chloride determination in food." Accreditation and Quality Assurance 11, no. 1-2 (March 31, 2006): 23–28. http://dx.doi.org/10.1007/s00769-006-0116-x.
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Zhang, Wei. "Research on Compressive Properties of Sea Sand Concrete." Advanced Materials Research 881-883 (January 2014): 1221–24. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1221.
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The chloride ion concentration of sea sand were measured by Volhard method and identified the method of removal chloride ions in sea sand. By comparison of compression test for sea sand concrete and river sand concrete ,two compressive strength performance is basically the same , Verify the feasibility of the concrete of the treated sea sand for bluiding.
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Wang, Yong Zheng, Lei Jiang, Mao Zhen Yue, and Su Fang Bian. "Study on Detection Methods for Chlorine Precipitation during Biomass and Coal Co-Combustion." Applied Mechanics and Materials 229-231 (November 2012): 1423–26. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.1423.
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In this paper, three detection methods were analyzed to determine the chlorine precipitation from the flue gas: Silver nitrate volumetric analysis (SNVA), Volhard method (VM) and Mercuric thiocyanate spectrophotometric method (MTSM). Results indicated that SNVA and VM were simple and convenient, but unsuitable for the detection of blend fuel due to the high lower limit. MTSM was suitable for biomass and coal co-combustion for its low lower limit and high sensitivity. In addition, MTSM needed less sample solution, which made it more suitable for multiple measurements to reduce errors, and the maximum proportional error was only 3.5%.
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El Ati, Jalila, Radhouene Doggui, and Myriam El Ati-Hellal. "A Successful Pilot Experiment of Salt Reduction in Tunisian Bread: 35% Gradual Decrease of Salt Content without Detection by Consumers." International Journal of Environmental Research and Public Health 18, no. 4 (February 8, 2021): 1590. http://dx.doi.org/10.3390/ijerph18041590.
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As bread is the most consumed food by the Tunisian population and the major source of salt, a pilot experiment of salt reduction in bread was begun in Bizerte city. Salt analysis in bread collected from Bizerte city was done with the Volhard titration method. A one-way Anova test was carried out to assess salt content changes over time. Application of the salt reduction programme allowed a gradual decrease of salt content in bread by 35% during three years without detection by Tunisian consumers. The salt concentration in bread was then reduced from 1.7 ± 0.2 g/100 g to 1.1 ± 0.1 g/100 g (p < 0.0001). The establishment of an effective salt reduction strategy with lifestyle education is needed to reduce hypertension, which is the primary cause of death in Tunisia.
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Lumbantobing, Ria, Mery Napitupulu, and Minarni R. Jura. "Analysis of Cyanide Acid Content in Cassava (Manihot esculenta) Based on Storage Time." Jurnal Akademika Kimia 8, no. 3 (September 24, 2020): 180–83. http://dx.doi.org/10.22487/j24775185.2019.v8.i3.pp180-183.
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Cassava is a tuber of cassava plants which is a source of carbohydrates that can be consumed as food and as snack foods such as chips. However, cassava and the leaves contain cyanide acid (HCN) which is dangerous for the human when consumed in excess. Cyanide acid reduction can be done by washing as well as immersion because of its volatile nature. The aim of this research is to investigate the difference of cyanide acid (HCN) content on peeled and unpeeled cassava with the variation of storage time 0, 2, 4, 6, and 8 days. A preliminary test was done to know the existence of cyanide acid (HCN) in cassava. Method analysis of cassava was titrated with the NH4CNS solution using the argentometric principle of the Volhard method. The results showed that cyanide acid (HCN) content in peeled cassava was higher than unpeeled cassava which was 3.9, 4.7, 5.2, 5.6, and 6.0% respectively for shelled cassava and 3.9, 4.6, 5.1, 5.5, and 5.9% respectively for unpeeled cassava.
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Bennett, James G., Stephen L. Kessel, and Charles E. Rogers. "Corrosivity Test Methods for Polymeric Materials. Part 3- Modified DIN Test Method." Journal of Fire Sciences 12, no. 2 (March 1994): 155–74. http://dx.doi.org/10.1177/073490419401200203.
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This is the third in a series of papers to investigate corrosivity test methods published by the Polyolefins Fire Performance Council, an operating unit of The Society of the Plastics Industry, Inc. In the first paper, 24 polymeric materials were evaluated for smoke corrosivity following the "Stan dard Test Method for Measuring the Corrosive Effect of Smoke from the Burn ing or Decomposition of Materials and Products" proposed by ASTM E05.21.70 which uses a radiant combustion/exposure apparatus. The second paper dis cussed the evaluation of the same 24 materials using the CNET corrosion test method "Plastics-Smoke Generation-Determination of the Corrosivity of Fire Effluents (Static Method)" under consideration by ISO TC61/SC4/WG2 and IEC TC89/WG3 and compared the CNET combustion results with the ASTM E05.21.70 results. In this paper, the 24 polymeric materials were evaluated us ing a modified "Testing of Cables, Wires and Flexible Cords; Corrosivity of Combustion Gases DIN 57 472 Part 813 Standard" acid gas test method and the results are compared to the previous ASTM E05.21.70 and CNET results. These commercially available polymeric materials cover a broad range of com positions used for wire and cable insulation and jacketing. The samples were decomposed in a modified DIN apparatus under dynamic conditions and the combustion gases were absorbed in a water trap where the pH and the conductivity were measured. The DIN apparatus was modified by the addition of gas dispersion frits for improved absorption of the combustion gases in the aqueous solution. The acid content of the aqueous solutions was determined using a silver nitrate/ammonium thiocyanate Volhard titration. The data demonstrate that the modified DIN test method using these indirect determinations of corrosive potential does differentiate polymeric materials, ranking them in a similar order to the ASTM E05.21.70 test method. Little cor relation with the CNET % Corrosivity Factor "COR" was found. Reasons for these differences are discussed. To complete the review of corrosion test methods, studies are under way to evaluate these same 24 materials with the "Fire Response Standard for Deter mining the Corrosive Effect of Combustion Products Using a Cone Corro simeter" proposed by ASTM D09.21.04.
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Li, Tian, Yuanyuan Zhang, Zhiyong Song, Hongtao Wu, and Shuhao Li. "Preparation and characterization of antibacterial silver loaded montmorillonite under microwave irradiation." Science and Engineering of Composite Materials 20, no. 1 (February 1, 2013): 15–22. http://dx.doi.org/10.1515/secm-2012-0060.
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AbstractSilver loaded montmorillonite (Ag-MMT) was prepared by ion exchange reaction under microwave irradiation. The effects of microwave irradiation time, AgNO3 concentration, and microwave power on the silver content of Ag-MMT were investigated using the Volhard method. The time of ion exchange reaction was found to be greatly shortened under microwave irradiation. The most suitable reaction condition was in 0.2 m AgNO3 under 100% microwave power irradiation for 4 min, and the silver content was determined and was found to be 1.23 wt%. The results of the Fourier transform infrared spectrum (FT-IR) and Ag+ release tests confirmed the successful loading of silver and its good slow-release property. The X-ray diffraction (XRD) patterns and ultraviolet-visible (UV-vis) spectra proved the existence of metallic Ag nanoparticles. The Ag-MMT showing a large inhibition zone, high inhibition ratio, and low minimum inhibitory concentration (MIC) value against Staphylococcus aureus ATCC6535 presented a very good antibacterial property.
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Martosuyono, Pujoyuwono, Asri Pratitis, Alexander Prasetya, and Elisabeth Kartika Prabawati. "DESALINATION OF CHITOOLOGOSACCAHARIDES USING GEL FILTRATION AND ULTRAFILTRATION." Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology 9, no. 3 (December 3, 2014): 127. http://dx.doi.org/10.15578/squalen.v9i3.110.
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Chitooligosaccharide (COS) , which is a derivative product from chitosan, has recently been used as a functional food because it has antimicrobial, antifungal, and antitumor properties. The salt content in chitooligosaccharide is one of the main problems in application as functional food or pharmaceutical medicine. The aim of this study was to remove salt from COS with two desalting techniques and determine the variation of COSs in the product. The desalting technique used were dialysis with 10kD Molecular Weight Cut Off (MWCO) and gel filtration chromatography HiPrep 26/10 desalting with G-25 Superfine Sephadex as stationary phase in the column. In order to detect the presence of COS, Thin Layer Chromatography (TLC) method was used, followed by Matrix-Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry (MALDI–TOF–MS) to detect low concentration of COS. Qualitative and quantitative analysis of salt presence were identified using silver nitrate and Volhard method respectively. Ash content was measured using gravimetric method. Results showed those dialysis and gel filtration chromatographies were successfully remove the most of the salt from COS with efficiency of desalting up to 100%. However, the best desalting technique was gel filtration chromatography HiPrep 26/10 which has more complete COS with various degrees of polymerization present in the result.
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Bosnea, Loulouda, Antonia Terpou, Eleni Pappa, Efthymia Kondyli, Marios Mataragas, Giorgos Markou, and George Katsaros. "Incorporation of Spirulina platensis on Traditional Greek Soft Cheese with Respect to Its Nutritional and Sensory Perspectives." Proceedings 70, no. 1 (November 10, 2020): 99. http://dx.doi.org/10.3390/foods_2020-07600.
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Spirulina platensis, the most popular microalgae species known for its high protein content and bioactive compounds such as phycocyanin and allophycocyanin, has been studied for cheese fortification. Incorporation of spirulina in dairy products poses major sensorial challenges due to its characteristic odor and its insolubility in food formulation, thus limiting consumer acceptance. The main objective was the production of a novel spread cheese fortified with spirulina, so powdered spirulina was added at different concentrations (0.25, 0.5, and 1%), and the effect on physicochemical, microbiological, and sensory characteristics was assessed. Cheese samples were examined for pH, fat (Gerber-Van Gulik method), salt (Volhard method), protein (Kjeldahl), and moisture content by drying to constant weight at 102 ± 1 °C. Cheeses were also assessed organoleptically by five experienced panelists. Generally, the addition of spirulina slightly increased the protein content and affected the color of the cheeses. The cheeses achieved a good microbiological profile and were all characterized as acceptable for consumption by the panelists. However, the cheeses with 0.25 and 0.5% spirulina were mostly preferred by the evaluation panel due to the less intense characteristic odor and taste of spirulina. We conclude that it is possible to produce an acceptable spread cheese with the addition of spirulina without significant changes in the cheese production line.
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Purwati, Yeni, Anny Thuraidah, and Dinna Rakhmina. "Kadar Sianida Singkong Rebus dan Singkong Goreng." Medical Laboratory Technology Journal 2, no. 2 (December 31, 2016): 46. http://dx.doi.org/10.31964/mltj.v2i2.93.
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<p style="text-align: justify;">Cassava is the third staple food often used by people to make a variety of products. Carbohydrates from cassava also contains toxic compound such as cyanide which can inhibit the action of respiratory enzymes. Cyanide in cassava can be removed by boiling or frying process. The aim of research was to find out the cyanide level differences between boiled cassava and fried cassava. This type of research was experiment, with design of comparative studies approach. Cyanide levels were examined in 10 samples with 2 treatments using Argentometry Volhard titration method. The result showed the average of cyanide levels in boiled cassava was 0.772 ppm and in fried cassava was 1.069 ppm. The percentage of cyanide levels reduction in boiled cassava was 28,78%, while for the fried cassava was 0%. The statistical test obtained the value of p <0.05, that showed there was significant difference of cyanide level between boiled cassava and fried cassava. Based on these results, it is advisable to choose the boiling process for cassava consumption. Next research can be conducted on comparative levels of cyanide in the cassava root and cassava leaves.
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Paraguassu-Chaves, Carlos Alberto, Cláudio José Pinto de Faria, Filomena Maria Minetto Brondani, Vera Lúcia Matias Gomes Geron, Nelson Pereira Silva Junior, Izan Fabrício Neves Calderaro, Fabrício Moraes de Almeida, and Leonardo Severo da Luz Neto. "Comparative Study of the Efficiency of Sodium Hydroxide, Sodium Hypochlorite and Sodium Chloride as Extractors of Residual Silver From X-Ray Plates and Graphical Effluents by the Volhard Method." International Journal of Advanced Engineering Research and Science 6, no. 2 (2019): 144–51. http://dx.doi.org/10.22161/ijaers.6.2.18.
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Rojanarata, Theerasak, Kwanrutai Waewsa-Nga, Parin Buacheen, Praneet Opanasopit, and Tanasait Ngawhirunpat. "Development of Greener and Safer Assays for Hydrochloride Drugs: Photometric Microtitration of Phenylpropanolamine Hydrochloride and Metformin Hydrochloride." Advanced Materials Research 361-363 (October 2011): 1892–96. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.1892.
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An environmentally friendlier, safer and saver method is described for the assay of drugs as hydrochloride salts namely metformin hydrochloride and phenylpropanolamine hydrochloride via the determination of their chloride contents. In this method, an aqueous solution of drug was treated with measured excess of silver nitrate in the presence of nitric acid, followed by the determination of unreacted silver nitrate by Volhard’s method using ammonium thiocyanate titrant and iron(III) alum indicator. To minimize the reagents consumed and wastes generated, the reactions were scaled down to less than 2 mL carried out in microcentrifuge tubes and using micropipettes for the transfer of reagents. The equivalence point was determined by spectrophotometry to diminish visual errors by reading the absorbance of red iron(III) thiocyante complex at 450 nm on microplates, which quickened the measurements of multi-samples. After validation, the method showed satisfactory accuracy and precision and was successfully applied for the assay of both drugs in raw materials, giving the results comparable to the pharmacopeial methods. In addition, the proposed assay was free from the use of harsh, toxic and environmentally harmful chemicals i.e. glacial acetic acid, acetic anhydride, mercuric acetate which are employed in the USP non-aqueous titration methods. Thus, the method is considerably safer for analysts and is a cost-effective and green analytical method suitable for a sustainable environment.
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Shahbazian, Ahad, and Malikeh Beheshtifar. "Employee Psychological Empowerment Models and Teaching ways of the Method." Revista Tempos e Espaços em Educação 13, no. 32 (March 2, 2020): 1–25. http://dx.doi.org/10.20952/revtee.v13i32.13180.
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Although individuals have the potential of showing more creativity, innovation, and performance, these capabilities are not exploited optimally in the organizational environment. Psychological empowerment of human resources has been known as an effective strategy in functioning and enhancement of human resources in transition management so educating the method is of great importance. Accordingly, the present study was conducted to analyze employee psychological-empowerment models and the ways of educating that. The paper was theoretical. The concept of empowerment and empowerment models were dealt with based on approaches using library method to realize the purpose of the paper. Then the empowerment models by (Bowen & Lawler, 1992), (Kanger & Kanengo, 1988), (Avolio, 2004), (Nokelainen & Ruhotie, 2003), (Dennis, 1984), (Robbins et al, 2018), (Villegas, 2019), (Vogt & Murrel, 1990), (Noller, 1997), (Thomas & Volhaus, 2017), (Spritzer, 1995), Iran Human Resources Empowerment Model, and so on were analyzed. After the analysis of the models, the effective model of employee psychological empowerment was extracted, involving the components of organizational culture, organizational structure, organizational monitoring system, organizational reward system, and the organizational management systems. Some aspects were considered for each component according to the conducted analyses and studying and comparing the models developed in this regard.
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Shahbazian, Ahad, and Malikeh Beheshtifar. "Employee psychological empowerment models and teaching ways of the method." Revista Tempos e Espaços em Educação 13, no. 32 (March 19, 2020): 1–25. http://dx.doi.org/10.20952/revtee.v13i32.13267.
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Although individuals have the potential of showing more creativity, innovation, and performance, these capabilities are not exploited optimally in the organizational environment. Psychological empowerment of human resources has been known as an effective strategy in functioning and enhancement of human resources in transition management so educating the method is of great importance. Accordingly, the present study was conducted to analyze employee psychological-empowerment models and the ways of educating that. The paper was theoretical. The concept of empowerment and empowerment models were dealt with based on approaches using library method to realize the purpose of the paper. Then the empowerment models by (Bowen & Lawler, 1992), (Kanger & Kanengo, 1988), (Avolio, 2004), (Nokelainen & Ruhotie, 2003), (Dennis, 1984), (Robbins et al, 2018), (Villegas, 2019), (Vogt & Murrel, 1990), (Noller, 1997), (Thomas & Volhaus, 2017), (Spritzer, 1995), Iran Human Resources Empowerment Model, and so on were analyzed. After the analysis of the models, the effective model of employee psychological empowerment was extracted, involving the components of organizational culture, organizational structure, organizational monitoring system, organizational reward system, and the organizational management systems. Some aspects were considered for each component according to the conducted analyses and studying and comparing the models developed in this regard.
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Alary, J., P. Bourbon, C. Escrieut, and J. Vandaele. "Improvement of end point-detection in Volhard's method for the titration of low level of chloride ion." Fresenius' Zeitschrift für analytische Chemie 322, no. 8 (January 1985): 777–78. http://dx.doi.org/10.1007/bf00489400.
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Polak, Tomaž, and Blažka Primožić. "Acceptance of liver pâté with reduced content of salt and sodium." Meso 20, no. 5 (2018): 384–93. http://dx.doi.org/10.31727/m.20.5.3.
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Akzeptanz von Leberpastete mit reduziertem Salz- und Natriumgehalt Ziel dieser Untersuchung bestand darin, eine Leberpastete mit einem reduzierten Anteil von Salz, akzeptablen sensorischen Eigenschaften und einer angemessenen Textur herzustellen. Der Anteil von Natrium in den Pasteten wurde durch die Zugabe von geringeren Mengen an Phosphatadditiven (0,15 %) und durch Reduktion der Menge von Meeressalz oder Nitritpökelsalz von 1,7 % auf 1,0% erreicht. In der Kontrollprobe der Leberpastete, hergestellt mit 1,4% Pökelsalz, wurde der Gehalt von Proteinen, Fetten, Mineralstoffen und Wasser festgelegt. Neben der Beurteilung der sensorischen Eigenschaften (deskriptive Analyse), wurden für alle Gruppen der Leberpasteteproben die chemischen Parameter festgelegt (der Gehalt von Natrium wurde anhand von ionenselektiven Elektroden und von NaCl nach der Volhard-Methode festgelegt), während die Trennung von Fetten und Wasser in der Emulsion und die Parameter Farbe und Textur durch Instrumente gemessen wurden. Die Pasteten, die mit diversen Sorten und Anteilen von Salzen und Phosphaten hergestellt wurden, unterschieden sich erheblich in ihrer chemischen Zusammensetzung, in den Farb- und Texturparametern, gemessen mit Instrumenten, und den sensorischen Eigenschaften (Farbe, Salzigkeit, Aroma, Textur und allgemeine Akzeptanz). In Anbetracht der Farbe der Leberpastete empfiehlt es sich, Pökelsalz zu verwenden, weil es der Pastete eine rosige Farbe verleiht, während die Verwendung von Meeressalz eine hellere Farbe der Pastete verursacht. Das Pökelsalz wirkt sich auch auf die Intensität eines besseren Aromas und die Akzeptanz im Allgemeinen aus. Die mit Phosphaten zubereiteten Pasteten sind weniger salzig, verursachen eine geringere Trennung von Fetten und Wasser und sind fester als die Pasteten, die ohne Phosphate hergestellt wurden, obwohl eine zu feste Textur bei Pasteten nicht wünschenswert ist. Der Anteil der Salze in der Pastete kann auf 1,2% (Nitritsalz) oder 1,0% (Meeressalz) reduziert werden, wobei, abhängig von der Art des Salzes und der Zugabe von Phosphatadditiven, der Anteil von Na+ um 11 % - 27 % reduziert wird. Pasteten mit einem Anteil von Nitritsalz von 1,5 % und Pasteten mit 1,3 % - 1,5 % Pökelsalz und zugegebenen Phosphaten sind mit der Kontrollgruppe, die die beste Akzeptanz gezeigt hat (1,4% Nitritsalz), am vergleichbarsten (lineare Diskriminanzanalyse).
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Korotkov, I. "PROBLEMS OF CONCENTRATION DETERMINATION OF INORGANIC ACIDS IN A MIXTURE WHILE RESEARCH ON EXAMINING OBJECTS." Theory and Practice of Forensic Science and Criminalistics 22, no. 2 (July 3, 2020). http://dx.doi.org/10.32353/khrife.2.2020.28.
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Inorganic acids are offered for forensic examination of materials, substances and products mainly in the form of individual aqueous mixtures, however, some of the objects are mixtures containing strong and weak acids or two strong acids, which complicates the process of determining the concentration of each component. For that reason creation of an accurate, correct, reproducible, rapid and simple methodology for determining mass fraction, in particular of sulfuric and hydrochloric acids, is also an important step in a reliable forensic assessment of study results.
To establish applicability of the methods of gravimetric analysis and interpretation of its result for forensic examination, research was carried out on a model three component mixture containing 10 % hydrochloric and 40 % sulfuric acid in an aqueous solution. Determination of sulfuric acid was implemented by means of gravimetric analysis: deposition of SO42-ions by Ba2+ ions with further calculation of acid mass fraction which is 39,05 ± 0,99% that is within the limits of an admissible error (Δхmax ≤ 3σ). The hydrochloric acid was determined by the Volhard method, according to the results of which the mass fraction of acid was 9,56 ± 0,45%, which is within permissible error limits (Δхmax ≤ 3σ).
Taking into account availability of equipment, simplicity, technological effectiveness, the suggested method for analyzing objects offered for research is an effective method for forensic monitoring of inorganic acids content which are the subject to control measures.
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Pargar, F., D. A. Koleva, E. A. B. Koenders, and K. van Breugel. "Monitoring the Electrochemical Response of Chloride Sensors Embedded in Cement Paste." MRS Proceedings 1768 (2015). http://dx.doi.org/10.1557/opl.2015.323.
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ABSTRACTThis work presents the electrochemical behavior of Ag/AgCl electrodes (chloride sensors) in cement paste environment, monitored over a period of 180 days via open circuit potential (OCP) readings and electrochemical impedance spectroscopy (EIS). The EIS response indicates modification of the sensors’ morphology, in particular alteration of the AgCl layers, as a result of continuous chloride penetration into the bulk matrix towards the vicinity of the sensor/cement paste interface. A gradual shift to more cathodic OCP values and stabilization at approximately -1mVSCE to 2mVSCE was observed at the end of the test, reflecting chloride content of 820mM to 930mM in the pore solution surrounding the sensors, which differs 5-10% from the chloride concentration in the external solution. The water soluble chloride content in the cement pate, as destructively measured wet chemically by Volhard method and photometry, was in the range of 1100mM - 1300mM i.e. about 30-50% more than the chloride concentration in the external solution. This difference of maximum 50% in the recorded chloride levels is attributed to the fact that the sensors “read” the average amount of free chloride at the interface sensor/cement paste, while the destructively measured water soluble chloride reflects the average free (with possible contribution of physically bound chloride) in the total volume of analyzed cement paste. It can be concluded that for the conditions of this experiment, more reliable free chloride content is measured via the sensors’ readings. Hence, if chloride thresholds for corrosion initiation are to be determined, the sensors’ readings will be more representative and accurate if compared to destructive water soluble chloride determination.
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Setyawardani, Dwi Ardiana. "PENGOLAHAN BIJI KARET SEBAGAI BAHAN BAKU PEMBUATAN MINYAK PANGAN (EDIBLE OIL)." EKUILIBIUM 12, no. 1 (January 1, 2013). http://dx.doi.org/10.20961/ekuilibrium.v12i1.2174.
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<p>Abstract: Rubber (Hevea Brasiliensa)is one of Indonesia's largest plantation commodities is not<br />optimal utilization. Rubber seeds have a high vegetable oil content of 45.63%, so the potential to<br />be used as edible oil. However, toxic linamarin contained in the seeds of an obstacle in the<br />utilization of rubber, because if hydrolyzed to form hydrogen cyanide (HCN), which if consumed<br />in large amounts can cause dizziness and fainting. Cyanide is soluble and evaporates. This study<br />aims to provide early treatment for rubber seed, in order to reduce levels of toxic linamarin. This<br />research is still exploratory, as a preliminary study for rubber seed oil to prepare adequate food<br />consumption. Linamarin removal process is done by soaking and boiling with variable immersion<br />1-3 days old, and the old variable boiling 1-2 hours. Rubber seed which has undergone initial<br />treatment further analyzed by the method of Volhard Argentometri way to determine levels of<br />linamarin contained therein. Furthermore, the oil extraction process is carried out using the<br />solvent n-hexane followed by degumming process and analysis of petroleum oil based food<br />quality standards (SNI 01-3741-2002)with parameters and acid value metal content. From the<br />research that has been done, the result that the greatest decline linamarin levels achieved at 1<br />day of immersion time and 1.5 hours of boiling time, ie by 39%. The results of the metal analysis<br />showed that rubber seed oil rubber seed oil oils do not meet the quality standards of food because<br />it contains a metal content of 1.78 ppm Cu (oil food safe limit of 1 ppm)that required further<br />treatment to reduce levels of Cu, one how the adsorption process using a specific adsorber.<br />Keywords: Rubber, Linamarin, Edible Oil.</p>