Thermodynamic Properties of HFC-227ea

The density and speed of sound in gaseous and liquid 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea) have been studied by a -attenuation technique, an ultrasonic interferometer, and an isochoric piezometer method over the temperature range of 273 to 383K at pressures up to 3.5MPa. The purity of the samples used throughout the measurements are 99.99mol%. The pressures of the saturated vapor were measured over the same temperature range. The experimental uncertainties of the temperature, pressure, density, and speed of sound measurements were estimated to be within ±20mK, ±1.5kPa, ±0.2%, and ±(0.15–0.2)%, respectively. On the basis of the obtained data, the isobaric molar heat capacity of HFC-227ea was calculated for the ideal-gas state.  

新型彩色反射密度仪的开发

针对国外进口密度仪对我国印刷生产的局限性,开发研制适合我国印刷国情的印刷质量检测仪器--彩色反射密度仪,并概括介绍新型彩色反射密度仪的功能、原理、设计的创新点和在各个工艺过程中的应用.  

TCS230传感器在彩色反射密度测量中的应用

介绍了TCS230颜色传感器的特性,结合印刷密度测量的特点,给出了TCS230传感器在彩色反射密度计设计中的使用方法及电路。实验证明,该电路能较好地满足测量需要,实现了彩色反射密度的测量,且在稳定性和精度上达到了设计要求,为TCS230颜色传感器的使用提供了应用实例。  

Radio Isotope Method for Rapid Determination of Proppant Concentration in Working Mixtures Used in Hydraulic Fracturing of Oil and Gas Containing Strata

A radio isotope method for rapid determination of proppant concentration and a test measurement unit RIKP-01 constructed on the basis of it provides a relative error in determining proppant concentration of not more than ± 3.5% with a measurement time of 15 sec that is four times better than for the world leader, i.e., the firm Halliburton (USA).Translated from Izmeritel’naya Tekhnika, No. 3, pp. 68–70, March, 2005.  

Densitometer for measurement of the optical density of motion picture and photographic film

A specification of photometric problems is considered for the purpose of drawing up requirements for a densitometer for use in quality control of film products. One aspect of the requirements of these products is that it is necessary to measure the optical density of black/white as well as positive and negative color film. __________ Translated from Izmeritel’naya Tekhnika, No. 7, pp. 39–41, July, 2006.  

A vibrating tube flow densitometer for measurements with corrosive solutions at temperatures up to 723 K and pressures up to 40 MPa

A new version of a vibrating tube flow densitometer has been designed permitting measurements of density differences between two fluids in the temperature range from 298 to 723 K and at pressures up to 40 MPa. The instrument is equipped with a Pt/Rh20 vibrating tube (1.6-mm o.d.) and a Pt/Rh10 transporting tube (1.2-mm o.d.) permitting measurements with highly corrosive liquids. The period of oscillation of the tube is about 7.5 ms, with a typical stability better than 10⁻⁴% over about a 1-h period over the entire temperature interval. The calibration constantK at room temperature is about 530 kg·m⁻³·ms⁻², with a temperature coefficient of approximately −0.13kg·m⁻³·ms⁻²·K⁻¹, and is practically pressure independent. It can be determined by calibration with a reproducibility generally better than 0.1%. The instrument was tested with NaCl(aq) solutions in the temperature range from 373 to 690 K for density differences between sample and reference liquid ranging from 200 to 2 kg·m⁻³; the corresponding errors are believed to be below 0.3 and 5%, respectively. A highly automated temperature control maintains the temperature of the tube stable to within ±0.02 K.  

A new,accurate single-sinker densitometer for temperatures from 233 to 523 K at pressures up to 30 MPa

A new apparatus for density measurements of fluids in the entire range from gas to liquid densities is presented. The instrument is a single-sinker buoyancy densitometer designed in a completely new way. The buoyancy force exerted by the sample fluid on an immersed sinker (buoy) is transferred by a new type of magnetic suspension coupling to an analytical balance. In order to reduce drastically the linearity error of the (commercial) balance. a special basic load compensation is applied which also avoids any buoyancy ellèct of the laboratory air on the balance. The new single-sinker densitometer covers a density range from 10 to 200(1 kg - m ' at temperatures from 233 to 523 K and pressures up to 30 MPa. A special compact version of such a single-sinker densitometer can even he used at temperatures from 80 to 523 K at pressures up to 100 MPa. Test measurements on densities of carbon dioxide at 233, 360, and 523 K at pressures up to 30 MPa show that the estimated total uncertainty of ±0.02% to ±0.03% in density is clearly met.Invited paper presented at the Twellth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado. U.S.A.Author to whom correspondence should be addressed.