Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry最新文献_第9页

The Enthalpies of Combustion and Formation of Linear Polyethylene. 线性聚乙烯的燃烧焓和形成。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-09-01 DOI: 10.6028/jres.078A.038

Paul L Splitstone, Walter H Johnson

引用次数: 6

Spectrum of Doubly Ionized Praseodymium from 2107 Å to 10716 Å. 双电离镨的光谱从2107Å到10716Å。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-09-01 DOI: 10.6028/jres.078A.036

Jack Sugar

引用次数: 11

A Heat-Loss-Compensated Calorimeter: Theory, Design, and Performance. 热损失补偿量热计：理论、设计和性能

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-09-01 DOI: 10.6028/jres.078A.037

Steve R Domen, Paul J Lamperti

{"title":"A Heat-Loss-Compensated Calorimeter: Theory, Design, and Performance.","authors":"Steve R Domen, Paul J Lamperti","doi":"10.6028/jres.078A.037","DOIUrl":"10.6028/jres.078A.037","url":null,"abstract":"A new type of 3-body calorimeter for measuring absorbed dose produced by ionizing radiation is described in detail. All three bodies rise in temperature during irradiation, and the heat absorbed by the central core is measured by standard means. Only the central core is heated during electrical calibration, but the increased heat losses are compensated by measuring most of the heat lost to the surrounding jacket and automatically adding it to the heat retained by the core. The third body is a massive, thermally-floating shield, whose presence reduces the heat losses during irradiation, with a consequent increase in sensitivity and stability. A mathematical description of the calorimeter behavior is presented, along with a discussion of control and operation technique. In particular, it is shown how this 3-body calorimeter can be calibrated as a 1-body calorimeter, with large heat losses, or as a 2-body calorimeter, in the quasi-adiabatic mode. This calorimeter design decreases the effects of thermal gradients and at the same time provides the means to test for these effects. The results of these tests show that for this particular model, systematic errors caused by thermal gradients, during electrical measurements, are no larger than 0.1 percent. Errors in comparing an electrical run with an irradiation may be somewhat larger because of different temperature gradients within the system. It is also pointed out that the general design of this calorimeter is not restricted to measuring absorbed dose but can be applied to calorimetry in general.","PeriodicalId":17018,"journal":{"name":"Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry","volume":"78A 5","pages":"595-610"},"PeriodicalIF":0.0,"publicationDate":"1974-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6728491/pdf/jres-78A-595.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37751298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High Pressure Measurements of Density, Velocity of Sound, and Bulk Moduli of Pentane and 2-Methylbutane and Their Mixtures. 戊烷和2-甲基丁烷及其混合物的密度、声速和体积模量的高压测量。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-09-01 DOI: 10.6028/jres.078A.039

James C Houck

引用次数: 19

Long-Time Creep in a Pure-Gum Rubber Vulcanizate: Influence of Humidity and Atmospheric Oxygen. 纯橡胶硫化剂中的长时间蠕变：湿度和大气氧气的影响。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-09-01 DOI: 10.6028/jres.078A.040

Lawrence A Wood, George W Bullman, Frank L Roth

{"title":"Long-Time Creep in a Pure-Gum Rubber Vulcanizate: Influence of Humidity and Atmospheric Oxygen.","authors":"Lawrence A Wood, George W Bullman, Frank L Roth","doi":"10.6028/jres.078A.040","DOIUrl":"10.6028/jres.078A.040","url":null,"abstract":"Long-time creep of natural rubber cured with a sulfur-accelerator recipe containing no filler can be conveniently represented by a plot of (E - E 1)/E 1 = ΔE/E 1 with a double-abscissa scale showing log t and t. E is the elongation at any time t, after application of the load, and E 1 its value at unit time. Experimental data conform to the equation except for a more rapid rise preceding rupture. The constants A and B can be evaluated from only three observations-at the longest time (about 70 days), at one minute, and at an intermediate time. ΔE/E 1 is approximately linear with log t when t is less than 0.1(A/B) and approximately linear with t when t is greater than 4.343(A/B). The observed modulus was about 1.4 MPa and A was about 2.4 percent/(unit log t) when the atmosphere was a vacuum, dry N2, or dry air. The modulus was lowered very slightly and A became about 4 percent/(unit log t) when the air was saturated with water. B was raised from about 2 × 10-5 percent/min to about 20 × 10-5 percent/min when the vacuum or dry N2 was replaced by dry air and to about 50 × 10-5 percent/min when the air was saturated with moisture. A is considered to be related to physical relaxation, while B corresponds to a chemical reaction, probably oxidative degradation.","PeriodicalId":17018,"journal":{"name":"Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry","volume":"78A 5","pages":"623-629"},"PeriodicalIF":0.0,"publicationDate":"1974-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6728486/pdf/jres-78A-623.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37753193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Measured Enthalpy and Derived Thermodynamic Properties of Crystalline and Liquid Potassium Chloride, KCl, from 273 to 1174 K. 结晶和液态氯化钾KCl在273-1174K范围内测得的焓和导出的热力学性质。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-07-01 DOI: 10.6028/jres.078A.035

Thomas B Douglas, Ann W Harman

引用次数: 5

Prediction of the Viscosities of "Soda-Lime" Silica Glasses. “钠钙”硅玻璃粘度的预测。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-07-01 DOI: 10.6028/jres.078A.032

Kenneth C Lyon

引用次数: 22

A Method of Measuring the Solubilities of Hydrocarbons in Aqueous Solutions. 测量碳氢化合物在水溶液中溶解度的方法。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-07-01 DOI: 10.6028/jres.078A.028

Robert L Brown, Stanley P Wasik

引用次数: 0

The System NaCl-AlCl₃. 系统NaCl-AlCl3。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-07-01 DOI: 10.6028/jres.078A.033

Ernest M Levin, J F Kinney, R D Wells, J T Benedict

引用次数: 13

Simultaneous Measurements of Heat Capacity, Electrical Resistivity and Hemispherical Total Emittance by a Pulse Heating Technique: Zirconium, 1500 to 2100 K. 用脉冲加热技术同时测量热容、电阻率和半球总发射率：锆，1500~2100K。

Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry Pub Date : 1974-07-01 DOI: 10.6028/jres.078A.034

A Cezairliyan, F Righini

{"title":"Simultaneous Measurements of Heat Capacity, Electrical Resistivity and Hemispherical Total Emittance by a Pulse Heating Technique: Zirconium, 1500 to 2100 K.","authors":"A Cezairliyan, F Righini","doi":"10.6028/jres.078A.034","DOIUrl":"10.6028/jres.078A.034","url":null,"abstract":"Simultaneous measurements of heat capacity, electrical resistivity and hemispherical total emittance of zirconium in the temperature range 1500 to 2100 K by a subsecond duration, pulse heating technique are described. The results are expressed by the relations: <dispformula> <math> <mrow><msub><mi>C</mi> <mi>p</mi></msub> <mo>=</mo> <mn>36.65</mn> <mo>-</mo> <mn>1.435</mn> <mo>×</mo> <msup><mrow><mn>10</mn></mrow> <mrow><mo>-</mo> <mn>2</mn></mrow> </msup> <mi>T</mi> <mo>+</mo> <mn>6.624</mn> <mo>×</mo> <msup><mrow><mn>10</mn></mrow> <mrow><mo>-</mo> <mn>6</mn></mrow> </msup> <msup><mi>T</mi> <mn>2</mn></msup> </mrow> </math> </dispformula> <dispformula> <math><mrow><mi>ρ</mi> <mo>=</mo> <mn>87.95</mn> <mo>+</mo> <mn>1.946</mn> <mo>×</mo> <msup><mrow><mn>10</mn></mrow> <mrow><mo>-</mo> <mn>2</mn></mrow> </msup> <mi>T</mi></mrow> </math> </dispformula> <dispformula> <math><mrow><mi>ϵ</mi> <mo>=</mo> <mn>0.2031</mn> <mo>+</mo> <mn>6.362</mn> <mo>×</mo> <msup><mrow><mn>10</mn></mrow> <mrow><mo>-</mo> <mn>5</mn></mrow> </msup> <mi>T</mi></mrow> </math> </dispformula> where C p is in J · mol-1 · K-1, ρ is in 10-8 Ω · m, and T is in K. Estimated inaccuracies of the measured properties are: 3 percent for heat capacity, 2 percent for electrical resistivity and 5 percent for hemispherical total emittance.","PeriodicalId":17018,"journal":{"name":"Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry","volume":"78A 4","pages":"509-514"},"PeriodicalIF":0.0,"publicationDate":"1974-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6742810/pdf/jres-78A-509.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37751297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3