提高梳理性能的简易途径

为了降低纺织厂的生产成本,充分利用原有设备的潜力,提高成纱质量,分析了老机改造加装前、后固定盖板的优势所在,并对比分析了改造前后的经济效益。指出安装棉网清洁器的必要性,给出了针布磨砺周期的参考数据及注意事项,可供一线管理人员参考。     

SOLUBILITY OF CO2AND H2S IN A MIXED SOLVENT

Mixed solvents are a combination of chemical and physical solvents and have some advantages over traditional treating solvents for the removal of acid gases from gas streams. The solubility of H₂S and CO₂in a mixed solvent consisting of AMP (2-amino-2-methyl-l-propanol), sulfolane, and water has been measured at 40 and 100°C at partial pressures of the acid gas to 6000 kPa. The solubility in the mixed solvent was compared with the solubility in an aqueous solution of equivalent amine concentration. At solution loadings less than 1 mol acid gas/mol amine, the solubility of the acid gas is lower in the mixed solvent than in the corresponding amine solvent. At higher loadings, the trend is reversed and the solubility is greater in the mixed solvent. The results are rationalized in terms of the effect of the physical solvent component on the chemical reaction and physical vapor-liquid equilibria. The solubility model of Deshmukh and Mather was used to correlate the data.     

Developments in membrane technology

Reverse osmosis and ultrafiltration of whey are commercially successful techniques for adding value to whey. Advances in membrane performance and plant configuration have improved the efficiency of reverse osmosis for whey concentration to a level significantly greater than that of conventional evaporation. Ultrafiltration of whey k also well proven and can provide a range of protein products of diverse composition and functionality.     

Sensory properties of low fat cheddar cheese:effect of salt content and adjunct culture

The influence of salt concentration and of direct-to-vat culture adjuncts (DVCA) on the sensory properties of low fat hard cheese of the cheddar type has been investigated. Salt content has a major influence, and, at a level of 1·8%, low fat cheese with high levels of cheddar flavour and low bitter scores was produced. In addition, further enhancement of flavour was achieved by use of DVCA. Using the methodology described in this report, low fat cheese was manufactured which corresponded in flavour level and balance to that of commercial mature full fat cheese. Nevertheless, textural differences between low fat and full fat product remain to be resolved.     

INSTRUMENT FOR MEASURING BIND STRENGTH OF RESTRUCTURED AND EMULSION-TYPE MEAT PRODUCTS1

A sensitive and inexpensive penetrometer is described, consisting of a mounted rod and polished steel ball that may be advanced downward at variable speed through meat slices mounted on a plexiglass cylinder. The slice + mounting cylinder was placed on a top-loading balance, tared to zero, and centered under the penetrometer rod. Bind strength was measured as the peak force (g) required for the steel ball advancing at 2.0 cm/min to penetrate the meat slice. Data points (grams force versus time) were collected and plotted using an IBM-compatible personal computer and printer. Since the balance collected gram values continuously, a QuickBasic program was developed, allowing the user to specify the time interval (1,2,5 s, etc.) between recorded values. Bind strength of turkey rolls was increased by finely chopping the emulsion (vs. coarsely-ground samples), and by inclusion of 3% nonfat dry milk. Whey protein concentrate (3%) increased bind strength of finely chopped, but not coarsely ground rolls.     

CO2-Catalyzed Surface Area and Porosity Changes in High-Surface-Area CaO Aggregates

The changes in surface area and mesoporosity in aggregates of ∼0.01 μm cross-section CaO particles when heated in CO₂at 686°C were determined from N₂ adsorption isotherms. Initially, the surface area decreases rapidly with little change in porosity. When the surface area has decreased below ∼90 m²/g, surface area and porosity variations become consistent with expectations for coarsening by grain-boundary or bulk diffusion. The initial rapid decrease in surface area must result from CO₂-catalyzed surface diffusion, but the data suggest that surface diffusion is not rate-limiting. The rate-limiting step may be reaction of CO₂ to form surface CO₃^2- ions or decomposition of these ions to O^2- ions and CO₂ gas.     

Colonization of Beef Muscle Surfaces by Pseudomonas fluorescens and Pseudomonas fragi

Attached and unattached cell densities were determined for Pseudomonas fluorescens and Pseudomonas fragi growing on the surface of beef muscle stored at 4 and 25°C, in presence of NaCl, KCl, and CaCl₂. A mechanical rinsing procedure was developed for this purpose. Both species colonized the surface at both temperatures and were enhanced at low (4°C) temperature. Attached cells represented up to 90% of the total until a density of 10⁵-10⁶ CFU cm^?2 was reached. At that point, a proportion of attached cells to unattached cells declined but colonization of the surface continued. In presence of CaCl₂, ratios of attached to unattached cells did not decline, suggesting a significant role for the calcium ion in colonization. Ability to colonize meat surfaces may be a significant competitive advantage for meat spoilage bacteria such as Pseudomonas fragi and Pseudomonas fluorescens.