Determination Of Specific Gravity Research Articles

Ultrasonic Investigation of the Effect of Vegetable Shortening and Mixing Time on the Mechanical Properties of Bread Dough

Mixing is a critical stage in breadmaking since it controls gluten development and nucleation of gas bubbles in the dough. Bubbles affect the rheology of the dough and largely govern the quality of the final product. This study used ultrasound (at a frequency where it is sensitive to the presence of bubbles) to nondestructively examine dough properties as a function of mixing time in doughs prepared from strong red spring wheat flour with various amounts of shortening (0%, 2%, 4%, 8% flour weight basis). The doughs were mixed for various times at atmospheric pressure or under vacuum (to minimize bubble nucleation). Ultrasonic velocity and attenuation (nominally at 50 kHz) were measured in the dough, and dough density was measured independently from specific gravity determinations. Ultrasonic velocity decreased substantially as mixing time increased (and more bubbles were entrained) for all doughs mixed in air; for example, in doughs made without shortening, velocity decreased from 165 to 105 ms(-1), although superimposed on this overall decrease was a peak in velocity at optimum mixing time. Changes in attenuation coefficient due to the addition of shortening were evident in both air-mixed and vacuum-mixed doughs, suggesting that ultrasound was sensitive to changes in the properties of the dough matrix during dough development and to plasticization of the gluten polymers by the shortening. Due to its ability to probe the effect of mixing times and ingredients on dough properties, ultrasound has the potential to be deployed as an online quality control tool in the baking industry.

Understanding the Molecular Surface Charges of Asphalt or Clay Particles and Application in the Transportation and Oil Sands Industries

Abstract Asphalt binder is a mixture of many different types of molecules. At the molecular level, one can visualize the asphalt binder as a colloidal system with asphaltene molecules dispersed in oil with naphthene and polar aromatics. The functional groups of the asphaltene molecules are essential in keeping them dispersed as colloids. These polar functional groups include alcohol, amine, carboxylic, and phenolic groups. The polarity of asphalt molecules are very important in allowing them to adhere to the inorganic aggregates, which also bear charges at the surface. The application of this understanding to the aging of paving asphalt, asphalt modification, the Superpave direct tension test, aggregate specific gravity determination, ash as modifiers in asphalt, low-volume road chemical stabilization, and the oil sands industry are discussed.

Determination of ethanol and specific gravity in gasoline by distillation curves and multivariate analysis

The partial least-squares regression method (PLS) was employed to predict the amount of ethanol and specific gravity in automotive gasoline using distillation curves (ASTM-D86). Additionally, a comparison was made between regression coefficients of all the algorithms, after selecting the number of latent variables. The low values obtained for RMSEC and RMSEP, associated with high accuracy when compared to the standard methodologies (NBR-13992, ASTM-D4052 and D1298) showed that PLS was efficient to determine the ethanol content and specific gravity in gasoline, since the model contains samples of different gasoline compositions, thus reflecting the variety of fuel in the Brazilian market. In addition, the proposed method is low cost, time reducing and easy to implement, as it utilizes the results of a routine assay carried out to evaluate the quality of automotive fuel.

Changes in specific gravity as a sign of disturbed brain maturation in protein-deprived rats.

The specific gravity of the cerebral cortex of normal and protein-deprived rats aged 15, 21 and 25 days was determined. The increase in specific gravity seen in control rats in the course of their development was reduced in protein-deprived rats in the course of the period between 15 and 21 days of age. The results are in agreement with previous reports on delayed maturation of the brain in protein-deprived rats and indicate that determination of brain specific gravity may serve as a suitable screening method in situations when a disturbed brain maturation is suspected.

Determination of specific gravity of green Pinus taeda samples by near infrared spectroscopy: comparison of pre-processing methods using multivariate figures of merit

Near infrared diffuse reflectance was used for the determination of specific gravity in green Pinus taeda L. wood samples representing simulated increment cores obtained at breast height and merchantable green logs. The effects of using three pre-processing methods (second derivative, multiplicative scatter correction, and orthogonal signal correction) to reduce the scatter observed in the original spectra were evaluated. The effectiveness of each method was assessed in terms of the average predictive ability of the models and in terms of multivariate figures of merit derived from net analyte signal theory. Specific gravity was successfully modeled using green wood samples. No differences in predictive ability among models were found, although more parsimonious regressions were obtained using transformed spectra. The incorporation of figures of merit for the characterization of calibration models proved to be a valuable tool for understanding the effects of the pre-processing alternatives on the final results.

Multivariate data analysis for classification of pineapple maturity

A range of physical and chemical parameters were investigated for their efficacy in classifying pineapple according to maturity or the presence of marbling defects. The tests were conducted on a sample of 115 “Pattavia” cultivar pineapples which were later sorted into three sets according to their differing maturity levels based on translucent yellow area of the longitudinal cut-open surface, and a further set comprising marbled fruit. The destructive parameters that were measured included soluble solids content, titratable acidity and flesh firmness. Nondestructive measurement techniques including acoustic impulse response tests and specific gravity determination by means of water replacement were carried out on each sample. Discriminant analysis using a canonical discriminant function with leave-one-out cross validation was performed to segregate the fruits into each class. The classification into maturity and marbling classes was achieved using multiple parameters with overall performance of 75.7%. The specific gravity, stiffness coefficient ( f 3 2 m 2/3 where f 3 is the third resonant frequency at the peaks of the acoustic spectrum, and m is fruit weight) and the soluble solids content appeared to be the most important parameters for distinguishing pineapples into three main groups: (1) class A (more mature fruit), (2) class B (mature fruit), and (3) class C (less mature fruit) and class M (marbled fruit). In addition, class M could be separated from class C by the titratable acidity, the flesh firmness and the stiffness coefficients based on f 1. For classification of mere maturity class, the performance was improved to 77.0%. The maturity was showed to be characterized by the specific gravity, the acidity and the soluble solids content. In differentiation of maturity using only nondestructive parameters, the specific gravity again gave the highest correlation for discriminant score of the discriminant function 1. The total classification performance was 82.8%. The stiffness coefficients complemented the classification through the discriminant function 2.

Evaluation the Clinitek status™ automated dipstick analysis device for semiquantitative testing of canine urine

The aim of this prospective study was to evaluate the Clinitek status™ analyser using Multistix10SG™/Microalbustix™ dipsticks (all: Siemens Dx) for canine urine ( n = 101) compared to reference methods: visual reading (Combur9 dipstick, Roche), refractometry, microscopy, and quantitative protein/creatinine analysis (Pentra400, AxonLab). The automated analyses were done twice and visual tests were performed by two examiners. An excellent to good concordance was demonstrated between the first/second analysis with the Multistix10SG and the Combur9 dipstick, respectively with Cohen’s κ-values ranging from 0.776 to 1.000. Agreement between both dipsticks was good for glucose ( κ = 0.753), blood ( κ = 0.793), protein ( κ = 0.788), and moderate for bilirubin ( κ = 0.431) and ketones ( κ = 0.540). In 6/101 specimens, false positive ketone reactions were obtained with the Multistix10SG™. Multistix10SG™ could not be used for determination of pyuria or specific gravity. Semiquantitative/quantitative protein results correlated well ( ρ = 0.90) and creatinine measurements moderately ( ρ = 0.76). Due to automated data transmission to the laboratory information system, the Clinitek status™ is of advantage in veterinary laboratories/clinics.

Cystinuria: from diagnosis to follow-up

Cystinuria is an autosomal recessive disorder characterized by an impaired transport of cystine and dibasic aminoacids, lysine, arginine and ornithine in the proximal renal tubule and in the epithelial cells of the gastrointestinal tract. Recurrent cystine nephrolithiasis is the main clinical feature. Mutations in SLC3A1 and/or SLC7A9 genes, which are encoding respectively the rBAT and the b(0,+)AT proteins of the amino acid transport system, are responsible of this disorder thus inducing a high dibasic amino acid excretion. Diagnostic is based on stone analysis by infrared spectroscopy or microscopic examination of urine which may reveal typical cystine crystals. Quantitative cystine excretion, which may be assessed by aminoacid chromatography, is higher in cystinic patients. Molecular approach can identify mutations which are responsible of this pathology. Medical treatment is mainly based on hydratation and urine alkalinisation, with the addition of thiol derivative only in refractory cases. Follow-up based on pH and specific gravity determination in urine samples and cystine crystal volume measurement are used to optimally monitor the medical treatment of cystinuric patients. Even with medical management, long-term outcome is poor due to insufficient efficacy and low patient compliance. Many patients suffer from renal insufficiency as a result of recurrent stone formation and repeated surgical procedures.

Superpave and the Aggregate Industry

Abstract The Superior Performing Asphalt Pavement (Superpave) mix design system was developed under the Strategic Highway Research Program, which was completed in 1993. Superpave consists of new methodologies for evaluation and selection of hot mix asphalt (HMA) material constituents along with new laboratory compaction protocols. During Superpave development, significant research focused on the performance grade asphalt binder system and gyratory compaction development. In contrast, very little research was performed to determine those aggregate properties and specification requirements most closely related to HMA mix performance. In 2000, the aggregate industry prepared a white paper for, and at the request of, the Transportation Research Board Expert Task Group on Superpave Mixtures and Aggregates. The paper focused on discussion of aggregate related issues that presented challenges to the implementation and use of Superpave. Since the white paper was written, Superpave has undergone modifications (specifications and general use or practice) based on completed research and general knowledge obtained. Many Superpave modifications were addressed in varying degrees in the white paper, and it is now important to discuss the impact of these modifications on HMA performance and the aggregate industry. In addition, other aggregate related issues are presented and discussed, including inconsistent fine aggregate definition, influence of minus 0.075 mm sieve material on fine aggregate specific gravity determination, aggregate production and particle shape, and the influence of aggregate on dynamic modulus.

Evaluation of Test Equipment for Determination of Fine Aggregate Specific Gravity and Absorption

Concern has been expressed about the repeatability of the current AASHTO T 84 method for determination of fine aggregate specific gravity. Two new methods are available for determining bulk specific gravity and absorption of fine aggregates: the AggPlus system using the CoreLok device and the SSDetect system. In addition, a new automated Langley de-airing device is available for AASHTO T 84. The objectives of this study were (a) to evaluate the reproducibility of SSDetect, CoreLok, AASHTO T 84, and AASHTO T 84 with the Langley de-airing device and (b) to determine if either of the new systems would produce results statistically similar to those produced by the current AASHTO T 84 procedure. The AASHTO procedure, when used with the Langley de-airing device, gave similar results to AASHTO T 84 but with reduced variability. The SSDetect procedure produced the highest bulk specific gravity and lowest percent absorption followed by the CoreLok and AASHTO T 84 procedures. There was no significant difference in apparent specific gravity values. Increasing the cure time for the SSDetect procedure resulted in increased saturated surface dry mass.

Part 1: Aggregate Testing and Effect of Aggregate Properties on Pavement Performance: Evaluation of Test Equipment for Determination of Fine Aggregate Specific Gravity and Absorption

Concern has been expressed about the repeatability of the current AASHTO T 84 method for determination of fine aggregate specific gravity. Two new methods are available for determining bulk specific gravity and absorption of fine aggregates: the AggPlus system using the CoreLok device and the SSDetect system. In addition, a new automated Langley de-airing device is available for AASHTO T 84. The objectives of this study were (a) to evaluate the reproducibility of SSDetect, CoreLok, AASHTO T 84, and AASHTO T 84 with the Langley de-airing device and (b) to determine if either of the new systems would produce results statistically similar to those produced by the current AASHTO T 84 procedure. The AASHTO procedure, when used with the Langley de-airing device, gave similar results to AASHTO T 84 but with reduced variability. The SSDetect procedure produced the highest bulk specific gravity and lowest percent absorption followed by the CoreLok and AASHTO T 84 procedures. There was no significant difference in ...

Examination of Gamma-Ray Method for Measuring Bulk Specific Gravity of Hot-Mix Asphalt Concrete

Much attention has been given to the determination of bulk specific gravity (Gmb) of compacted hot-mix asphalt (HMA) specimens. For relatively open-graded HMA mixtures, such as those produced by Superpave® and stone matrix asphalt design methods, perceived potential shortcomings in traditional test methods may be pronounced. Recently, a new device was introduced for measuring Gmb that features the use of gamma-ray technology. To evaluate the efficacy of the device, 221 compacted HMA specimens were tested with three test methods: saturated surface dry (SSD) (AASHTO T-166), vacuum-sealing (Corelok), and gamma-ray technology (CoreReader). Each specimen was tested three times in each of the three methods. The specimens represented field-sampled and laboratory-prepared mixtures, 12.5-mm and 25-mm nominal maximum aggregate sizes, and a variety of aggregates typically used in Arkansas. Test results indicated that statistically significant differences exist between mean Gmb-values generated by each of the three testing methods. In general, the vacuum-sealing method yielded the lowest Gmb-values, followed (in order of low to high) by the gamma-ray and SSD methods. Significant differences in the variability of test results were not observed between test methods. In ease of testing and testing variability, the CoreReader gamma-ray device does not appear to offer significant advantages for determining the bulk specific gravity of compacted HMA cores. Further, departments of transportation wishing to replace or allow alternatives to traditional SSD-based tests should consider the impact of test results on existing volumetric property specifications.

An Alternative Approach for the Determination of Bulk Specific Gravity and Permeability of Hot Mix Asphalt (HMA)

The objective of this study was to investigate the use of an alternative method for determination of bulk specific gravity and estimation of water permeable voids of dense graded HMA mixes. As a part of an ongoing study on evaluation of permeability of HMA, several dense graded mixes with coarse and fine gradations from three New England states were compacted to produce mixes at different air voids. The bulk specific gravities of these mixes were determined using both the saturated surface dry method and the vacuum seal method. Theoretical maximum densities of these mixes were also determined. Air voids of the different compacted mixes were estimated from the bulk specific gravity and theoretical maximum density values. Porosity and permeability tests were also conducted on the mixes. The results showed that for coarse graded mixes and fine graded mixes with high air voids, the vacuum seal method provided a better estimation of air voids in a compacted HMA mix. For coarse graded mixes, porosity can provide a good indication of inter-connectivity of air voids in a compacted HMA mix. Analysis of the data showed that porosity could provide an excellent indication of permeability of HMA. A porosity of 7% seemed to be critical--mixes with porosity greater than 7% showed significantly higher permeability than mixes with porosity lower than 7%. Charts have been provided for selection of proper gradation and air voids to avoid mixes with excessive permeability.

Determination of Specific Gravity and Void Ratio of Pumice Materials

Abstract The vesicular nature and the soft grains of pumice deposits create difficulties in testing them and in interpreting the test results. This note examines the difficulty of measuring specific gravity and estimating void ratio. The difficulty arises from the presence in the particles of a network of internal voids or vesicles, some of which are interconnected and open to the external surface, while others are isolated inside the particle. The void ratio measured by conventional methods invariably includes some of the internal void space, and is therefore, not a true measure of void ratio in terms of the normal definition or understanding of the term. This paper examines different ways of measuring the specific gravity, and the influence of particle size on the results.

Curvas de porcentagem mássica de água versus peso específico em vegetais in natura - otimização de processos industriais pela seleção via teste da matéria-prima

The purpose of this investigation is to verify the existance of a relation between specific gravity (SG) and watermass percentage (WMP) in vegetables in nature. The curves of Solanum tuberosum (potato), Dioscorea sp (yam), Manihot utilissima (cassava) were plotted. The procedure of determination of specific gravity in laboratory can be used as a test in industrial scale to determine the water mass percentage in vegetables in nature that have uniform aspect through the curve SGxPMA of the vegetable. This test is simple, economic, not destructive and precise, so it’s easy to introduce in industries to improve the process that has vegetables in nature as raw materials, once water mass percentage of the vegetable is an important parameter. With this test application is possible to select the raw materials that make better productivity, allowing better products and bigger profit of the process, besides more homogeneous final products.

Effects of oral administration of concentrated equine serum IgG to newborn foals on passive immunity

Thirteen newborn foals of Quarter Horse breeding were used to determine if oral administration of concentrated equine serum increases concentrations of IgG in foals allowed to naturally suckle colostrum. Foals were alternately assigned either to receive 300 ml of an oral equine serum IgG product or to serve as controls. Foals receiving the IgG product were given 150 ml orally at 10 hours and again at 12 hours after birth. All foals were allowed to suckle from their dams ad libitum. Jugular blood samples were obtained from foals at 10 hours and 24 hours of age for IgG determination. Colostrum samples from the dam were also obtained within 3 hours following parturition for determination of specific gravity. Plasma samples were analyzed for IgG level using a commercially available radial immunodiffusion kit. Oral administration of equine serum IgG had no significant effect on concentrations of plasma IgG in foals at 24 hours of age (p>.34). There was also no difference between control and treated foals in the rate of IgG absorption from 10-24 hours after birth (p>.34). In conclusion, oral administration of equine IgG to foals that ingest their dam's colostrum does not significantly increase concentrations of plasma IgG when compared to controls.

Temperatures and Performance in a Tunnel-Ventilated, High-Rise Layer House

Temperatures were recorded from winter to summer in a high-rise, bidirectionally tunnel-ventilated commercial layer house. In cool weather, the house was ventilated through side wall baffle inlets and a series of ceiling inlets. The temperature sensors were located in the vicinity of the tunnel inlets (CENTER sites) near the ends of the house where the exhaust fans were located (END sites), and midway between these locations (INTERMEDIATE sites). Hens and eggs were weighed, and eggs samples for specific gravity determinations, once a month at the sites of the temperature sensors. In winter, the CENTER sites were coolest and the INTERMEDIATE sites tended to be warmest. In spring, there were no differences among areas in average daily temperature. During summer, CENTER sensors were again coolest and END sensors were warmest. CENTER sites had the largest eggs during the winter and summer months. INTERMEDIATE sites tended to have the smallest eggs from January to March. Egg size variation among different areas might have been minimized in winter by covering the tunnel curtain inlet, and in summer by using only information from the sensors nearest the fans to control fan operation when in tunnel ventilation mode. Hens in the lowest tier of cages consistently produced the largest eggs.

Use of pamidronate disodium to reduce cholecalciferol-induced toxicosis in dogs.

To determine whether pamidronate disodium can reduce cholecalciferol-induced toxicosis in a dose-related manner. 20 clinically normal, 8- to 12-month-old male Beagles. All dogs were given 8 mg of cholecalciferol (CCF)/kg of body weight once orally, then were randomly assigned to 4 groups of 5 dogs each. Dogs were treated with IV administration of 0.9% NaCl solution (SC group), 0.65 mg of pamidronate/kg in 0.9% NaCl solution (LP group), 1.3 mg of pamidronate/kg in 0.9% NaCl solution (MP group), or 2.0 mg of pamidronate/kg in 0.9% NaCl solution (HP group) on days 1 and 4 after administration of CCF. Dogs were observed for 14 days, and serial blood samples were collected for serum biochemical, electrolyte, and 25-hydroxyvitamin D3 analyses. Urine samples were collected for determination of specific gravity. Glomerular filtration rate (GFR) was determined by plasma iohexol clearance. Histologic examination of renal tissue was performed. One dog in the SC group was euthanatized 3 days after administration of CCF because of severe clinical signs of toxicosis. Dogs in the HP group had significantly higher mean GFR (day 3), serum potassium concentrations (day 14), and urine specific gravity (days 7 and 14) and significantly lower mean serum creatinine concentrations and total calcium X phosphorus concentration product (days 4 and 7) than dogs in the SC group. Dogs in the HP group had no abnormal findings on histologic examination of renal tissue, dogs in the LP and MP groups had trace to mild mineralization of renal tissue, and dogs in the SC group had moderate mineralization and cellular necrosis of proximal renal tubules. Pamidronate disodium is a potentially useful drug to reduce CCF-induced toxicosis and other causes of hypercalcemia associated with increased bone resorption in dogs.

Effect of bauxite properties on the settling of red mud

Abstract Most bauxite deposits are fossil soils in which gibbsite or boehmite are the ore minerals. In the alumina production process with sodium hydroxide (Bayer process), the ore minerals go into solution and the iron-oxide impurities remain insoluble (red mud tailings). The settling behaviour of the tailings is an important economic factor as it controls purity, and an important environmental factor as it controls final liquid content of the red mud tailings for disposal. In the Bayer process, the operating factors determining different settling rates are not at all clear. It is known that two bauxites from a few metres apart may produce muds with different settling rates. Thus, the mineralogical and chemical compositions of the bauxite would seem to be important factors in determining mud settlement patterns. In this work, a total of 7 bauxites and 7 red muds from Southern Brazil are examined for their mineralogical, chemical and physical properties by employing X-ray diffraction (XRD), X-ray fluorescence (XRF), dissolution technique (dithionite-citrate), inductively coupled plasma (ICP) and, Brunauer, Emmett and Teller (B.E.T.) specific surface area, for comparison with the measured settling behaviour of the muds. The results of this work reveal the differences in settling rates, and mineralogical, physical and chemical properties which exist among the studied red muds. Since there was no technological variation in the Bayer process used for the bauxites, these noticeable differences in settling behaviours of their derived red muds are due mainly to differences in their source bauxites. The mineralogical composition of the bauxite is one of the most important factors that significantly influences the red mud properties. Muds containing hematite, settle faster than those which contain goethite as the main iron mineral. Specific surface area and specific gravity determinations of the red mud indicate that the content of cryptocrystalline iron oxides and nature of their mineralogical composition may be used as a guide to settling rate. Amorphous and cryptocrystalline iron mineral is another significant factor in affecting the settling of the studied Brazilian red muds. This amorphous and cryptocrystalline iron (Fed) possibly acts as a bonding agent for the red mud particles and the synthetic flocculant.

Estimating Probable Maximum Floods in the Upper Santa Ana Basin, Southern California, From Stream Boulder Size

Large stream boulders in 16 drainage basins within the Upper Santa Ana basin were studied; 9 of these basins were in the Eastern San Gabriel Mountains and 7 were in the Western San Bernardino Mountains. A total of 43 sites were sampled. Field measurements included boulder dimensions, lithology for specific gravity (and particle density) determination, bed roughness, channel slope, and width. The five largest boulders at each site were selected. Field data were used in paleohydraulic calculations to determine, average velocity, average flow depth, and estimated discharge that would accompany boulder movement in a fluvial system. Tractive competence, the largest particle that can be moved in a stream bed, is velocity dependent, and flow depth is a function of velocity. Therefore, by selecting the largest stream boulders for study, flow velocity and depth at the time of boulder transport can be estimated. This information, used in conjunction with the stream channel cross section, can then be used to estimate conditions that only occur during the highest magnitude flood event: the probable maximum flood (PMF). The largest flood this century in the study area occurred in 1938. This study indicates that the PMF for the selected streams is approximately three times the discharge of the 1938 flood. This is generally in line with the peak flood discharge estimated by the slope-area method for the “Great Flood” of 1862.