THE PREPARATION AND SOME FLOW CHARACTERISTICS OF PLASTIC CASEIN

1938 ◽  
Vol 16b (10) ◽  
pp. 345-360 ◽  
Author(s):  
Wilfred Gallay ◽  
James S. Tapp

The preparation of rennet casein has been studied on both a laboratory and plant scale, and the effect of the various factors in procedure on the quality of the casein produced is discussed. The details of preparation for a product of excellent quality are given. A simple heat resistance test showing the presence of impurities has been developed. The plasticity of a number of caseins has been measured by a direct method in a laboratory extruder, under pressure ranging up to 77,000 lb. per sq. in.; the maximum viscosity measured directly in this study was about one billion, seven hundred million poises. The flow-pressure curves obtained show no tendency towards a yield point, but show varying degrees of structural viscosity and may be fairly well represented by the relation F = kPn, where F is the flow, P is the pressure, n and k are constants. Decrease in pH of the casein, decrease in ash, and increase in lactose content all lower the viscosity of plastic casein. Small increases in water content decrease the viscosity greatly. Up to 80 °C. the temperature of drying has no appreciable effect on the viscosity. Moistening of casein plastic is discussed, as is also the distribution of water and vapor equilibria. Plastic casein is shown to exhibit streamline flow in extrusion, and plasticization is therefore more difficult to accomplish.

2019 ◽  
pp. 357
Author(s):  
Matheus Pena Campos ◽  
José Carlos Moraes Rufini ◽  
Bruno Montoani Silva ◽  
Saulo Saturnino de Sousa ◽  
Deniete Soares Magalhães ◽  
...  

Pot capacity (PC) is a direct method of determining field capacity (FC) for experiments with plantings in pots. The objective of this study was to evaluate different laboratory methods to determine field capacity and compare them with the pot capacity method. The experimental design was completely randomized (CRD), with nine treatments (methods of obtaining FC) and four replications, totaling 36 experimental plots. The mean values of moisture contents in the FC of the nine methods were compared, being eight empirically obtained and one directly in the greenhouse, defined as a control treatment (PC). The relative accuracy (RA) for all treatments was determined in relation to the control treatment. The estimation of the upper limit of available water in the soil varies depending on the method, and a decreasing order of moisture levels can be observed at FC: FC-Lab4pts > FC-Labip > FC-Lab8pts > PC > FC-Lab6pts > FC-6KPa > FC-LabSWRC > FC-10KPa > FC-33KPa. The treatment FC-Lab6pts has the relative accuracy closest to 100% and can be a practical alternative to PC. The use of 4, 6, 8 or 10 points for modeling the SWRC does not interfere with the quality of the FC estimated by the Dexter inflection point method, which is much more efficient for experiments of this nature. The use of potentials -10 kPa and -33 kPa is not adequate to estimate FC in tests with pots in a greenhouse.


2008 ◽  
Vol 130 (5) ◽  
Author(s):  
Fumi Takeoka ◽  
Masaharu Komori ◽  
Aizoh Kubo ◽  
Hiroshige Fujio ◽  
Shigeaki Taniyama ◽  
...  

The vibration and noise of gears is one of the serious problems for devices, such as vehicles and wind turbines. The characteristics of the vibration and noise of gears are considerably affected by the tooth flank form deviation of micrometer order. The quality of product gears is controlled using a gear measuring instrument and calibrated with an involute artifact. However, the conventional calibration of the involute artifact cannot achieve a sufficient accuracy. In this report, a direct method of measuring the involute artifact using a laser interferometer is proposed. Fundamental experiments are carried out, in which the effects of the surface condition of the measured object and the effect of the driving of the artifact are investigated. It is confirmed that the proposed method enables the measurement of the detailed form of an involute tooth flank and has the potential of accomplishing a highly precise measurement of an involute artifact.


2021 ◽  
Vol 7 (17) ◽  
pp. eabf8283
Author(s):  
Sibao Liu ◽  
Pavel A. Kots ◽  
Brandon C. Vance ◽  
Andrew Danielson ◽  
Dionisios G. Vlachos

Single-use plastics impose an enormous environmental threat, but their recycling, especially of polyolefins, has been proven challenging. We report a direct method to selectively convert polyolefins to branched, liquid fuels including diesel, jet, and gasoline-range hydrocarbons, with high yield up to 85% over Pt/WO3/ZrO2 and HY zeolite in hydrogen at temperatures as low as 225°C. The process proceeds via tandem catalysis with initial activation of the polymer primarily over Pt, with subsequent cracking over the acid sites of WO3/ZrO2 and HY zeolite, isomerization over WO3/ZrO2 sites, and hydrogenation of olefin intermediates over Pt. The process can be tuned to convert different common plastic wastes, including low- and high-density polyethylene, polypropylene, polystyrene, everyday polyethylene bottles and bags, and composite plastics to desirable fuels and light lubricants.


2020 ◽  
Vol 36 (4) ◽  
pp. 955-961
Author(s):  
Rizky Zulkarnain ◽  
Dwi Jayanti ◽  
Tri Listianingrum

The increasing needs for more disaggregated data motivates National Statistical Offices (NSOs) to develop efficient methods for producing official statistics without compromising on quality. In Indonesia, regional autonomy requires that Sustainable Development Goals (SDGs) indicators are available up to the district level. However, several surveys such as the Indonesian Demographic and Health Survey produce estimates up to the provincial level only. This generates gaps in support for district level policies. Small area estimation (SAE) techniques are often considered as alternatives for overcoming this issue. SAE enables more reliable estimation of the small areas by utilizing auxiliary information from other sources. However, the standard SAE approach has limitations in estimating non-sampled areas. This paper introduces an approach to estimating the non-sampled area random effect by utilizing cluster information. This model is demonstrated via the estimation of contraception prevalence rates at district levels in North Sumatera province. The results showed that small area estimates considering cluster information (SAE-cluster) produce more precise estimates than the direct method. The SAE-cluster approach revises the direct estimates upward or downward. This approach has important implications for improving the quality of disaggregated SDGs indicators without increasing cost. The paper was prepared under the kind mentorship of Professor James J. Cochran, Associate Dean for Research, Prof. of Statistics and Operations Research, University of Alabama.


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